Introduction to watercolour

Delicate and translucent, watercolours have a unique luminosity and are capable of intensely saturated marks as well as subtle washes. The fluid nature of watercolour allows for exciting and unpredictable effects to be created.

Watercolour paint is made from finely ground pigment suspended in a binder made of distilled water and gum arabic (a gum that is extracted from two species of the acacia tree). After the water has evaporated from the paint as it dries, the gum arabic acts as the glue that binds the pigment to the paper. It also slows the movement of the watercolour when applied as a wash, and many artists add more gum arabic to their watercolour to gain control over their colour (to stop it from bleeding or spreading too quickly over a surface). 

Generally, the character of each watercolour colour tends to rely more heavily on the characteristic of the pigments used, and certainly more so than found in oils or acrylics, where the character of the binder itself plays a more significant role in contributing to the character of the paint overall. This is also true because colour is applied much more thinly, which allows for the characteristic of the pigment to be more apparent in the very thin paint film that is applied.

What do I need to start painting with watercolour?

With paper, paints and brushes, you have enough to make a watercolour painting. Simply add a jar of water and away you go! However there are also some other supplies you could invest in.

A selection or set of watercolour paints in either solid pans or in moist tubes

Brushes

Paper

Palette

Jar of water

Useful tools:

Easel

Masking fluid

Sponge

Board and gumstrip (for stretching paper)

Watercolour paint is available in tubes and dry, solid watercolour pans that become fluid paint on contact with a wet brush. For a beginner, a set of pans is a good way to start as pans are easier to use. Pans allow you to apply colour lightly and build it up in layers, whereas with tubes of paint there is a greater risk that you may apply too much colour too soon, which can be hard to control. As with all paint, as you gain experience you will inevitably develop preferences for certain pigments, but to start with, invest in a general set of watercolours so that you can explore a whole spectrum of colour.

An eight pan set of watercolours is considered small but will offer enough colours to get started painting any subject matter. However, most sets will contain 12 or 24 colours.

What are the main properties of watercolour?

Watercolourists tend to consider 3 key characteristics when choosing the pigments that they wish to work with:

Transparency/opacity
Staining capacity
Granulation/texture

Because watercolour is supposed to be applied in a relatively diluted state, it is rare to find watercolour applied so that it appears fully opaque, however, all pigments have their own degree of transparency/opacity which will have some bearing over how they mix with other pigments and how they appear on the surface when painted with. 

Staining refers to how much of the pigment will not lift from the paper after being blotted with a damp sponge. More modern pigments as well as some of the stronger traditional watercolour paints such as Prussian Blue and Alizarin Crimson tend to have a greater staining capacity whereas the older, more traditional pigments tend to lift with relative ease. 

Granulation refers to when the pigment particles do not dry with even spacing, and instead, they form pools of darker shades of colour when applied to a surface (be it paper or a canvas that has been primed with an absorbent ground) – in other words, the watercolour dries with a grainy appearance. This is caused by the characteristics of the pigments used – some are heavier and cannot be ground to as fine or as uniform a state as others can, and this causes the effect. There can also be a difference between the manner that pigments granulate – a fine pigment such as French Ultramarine will show flocculation – this is when the pigments rush together in huddles. A heavier pigment such as the ones used to make Permanent Mauve will simply fall into the hollows of the paper surface. The general rule to bear in mind is that while traditional pigments such as the earths, cobalts, and ultramarines granulate, the modern colours tend not to. A granulation medium can be added to colours to increase their tendency to granulate, if you wish to achieve this effect.

What is permanence?
You will find in some watercolour ranges that there will be some pigments that are not classified as lightfast – this means that they will fade if continuously exposed to sunlight on a wall in a room (they are not tested for exposure to strong sunlight outside). Not all watercolourists make paintings that are intended to be framed and hung on a wall, and because some pigments have a wonderful vibrancy and brilliance despite their poor lightfastness ratings, they are included in some ranges due to the demand. An example of this would be Opera Rose – this vibrant pink is extremely popular among botanical painters in particular, and because some botanical painters keep their work in books and portfolios, its permanence is of lesser importance, and this is why manufacturers such as Winsor & Newton and Sennelier include it in their ranges. If lightfastness is of great importance to you and your work, always consult the manufacturer’s colour chart to make sure the pigments you choose are less prone to fading.

What’s so good about single pigment colours?
Some paint colours are made of one pigment like Ultramarine Blue, while others are made of two or more pigments like New Gamboge. It is easier to mix bright and vibrant colours using single pigment colours. A combination of too many pigments will only ever achieve muddy or dull hues. This is because every pigment absorbs all the wavelengths of light except the colour it reflects back. Each additional pigment absorbs a different light. As the proportion of each pigment decreases when more are added, less colour is reflected from each and it’s a mixture of lots of colours.

Some colours can only be made with a combination of pigments – popular colours such as Quinacridone Gold have to be mixed as the original pigment is no longer available, and Permanent Alizarin Crimson is mixed so that there is a lightfast alternative to the traditional single pigment colour. 

Artist and Professional grade watercolours will have a larger proportion of single pigment colours in their ranges. 

Examples of these include Jackson's Professional Watercolour, Sennelier l'Aquarelle, Winsor & Newton Artists' Watercolour, Daler Rowney Artists' Watercolour, Schmincke Horadam, Holbein Artists' Watercolour, Daniel Smith Extra Fine Watercolour, Old Holland Classic Watercolours, Shin Han Artists' Watercolours, Blockx Artists' Watercolours, and Rembrandt Artists' Quality Extra Fine Watercolours. 

What’s the difference between professional and student grade watercolour?

The highest quality watercolour paints are known as professional (or artist) colour, and these will have the highest ratio of pigment to binder. The colour will be very intense in the pan or squeezed from the tube, and you will need less of it. The quality of the binder will also influence the quality of the paint. The binder can also be a question of preference. Sennelier and Jackson’s watercolour are both known to add honey to the binder as they believe it optimises the consistency of the paint, but some artists prefer the consistency of other professional grade colours that do not use honey – our suggestion is to try and see which brand works for you. 

The pigments used to make professional watercolour paint are expertly ground to an optimal size to show the individual characteristics of the colour - this varies from pigment to pigment, depending on the structure of the pigment particles. Larger or heavier pigment particles will result in a granulating colour and are often indicated on the manufacturer's colour charts. The ground pigments are slowly milled into the vehicle (a mix of gum arabic, water, a plasticiser such as glycerin, a humectant, dispersant, and extender), the pigments gradually becoming evenly dispersed within it. Eventually an equilibrium is met – a balance between pigment and binder which varies depending on the characteristics of each pigment. However, because of the weight of the pigment particles, over time they do on occasion sink to the bottom of the tube, leaving an excess of clear gum arabic at the top. If this happens, stirring the contents of the tube with a straightened paperclip can help to regain an even paint consistency.

Student grade watercolours will contain a lower concentration of pigment. As this is the most expensive ingredient in paint, this allows the paints to be more affordable.

In a student grade paint where pigment concentration is lower, how each colour behaves from pan to pan will be more consistent, which simplifies the painting process. When starting out, a student set is recommended as the quality is still good and it offers an economical introduction to the medium. This article by amateur artist Ann Cahill explains her experiences of working with both student and artist grade watercolours.

Student watercolour ranges are also more affordable because less expensive pigments are used in the colours and ‘hue’ colours (mixtures of other pigments) are used to replace expensive cobalt and cadmium colours. Student watercolours are more likely to have lower permanence ratings, but if this is of importance to you it is always worth consulting the colour chart. 

Examples of student watercolour include St. Petersburg White Nights Artists' Watercolour, Winsor & Newton Cotman Watercolour, Dr. Ph. Martin's, and Reeves.

What’s the difference between watercolour pans, tubes, and sticks?

Watercolours are available in tubes, pans, and sticks. Pans are plastic vessels in which dried watercolour is kept. Colour is taken from a pan by dragging a wet brush over it. Pans are very easy to carry about (in watercolour boxes) and convenient. Large pans are available for those who like to work on a large scale or use broad brush strokes.

Tubes contain moist watercolour, which can be squeezed into empty pans if so desired, or onto a palette. They are great if you want to premix a batch of colour to contain in pans. They are also very good for painters who like to work with very intense colour.

Pans
Watercolour pans come in two rectangular sizes: a full pan and a half pan (a full pan is sometimes called a whole pan). Across brands the sizes of pans are nearly the same standard size but not quite, so that’s why many watercolour boxes have bendable compartments that allow for slight adjustments to hold the pans. Travel watercolour boxes that do not have adjustable compartments will not work with all brands of pans because even a part of a millimetre difference means that they won’t fit in the slot. In the Holbein half pan sets the plastic pans come with a magnet on the bottom of each pan to hold it in place in the box.

A few brands do other sizes than the two common ones: Blockx do a Giant Pan (a generous 3.5 by 2.5 inches), Gansai Tambi are much larger than standard and Coliro do two sizes of round pans. Daler-Rowney does a delightful miniature set of 1/4 pans. To refill it you purchase extruded half pans and gently cut them in half with a craft knife.

Pans also vary in their formula and method of manufacture. Some pans are extruded like dough, cut into cubes, let to dry, and then placed into pans as a hard cake. These can often be seen sticking up above the rim of the pan. Those that are poured also vary. Some are poured once and allowed to shrink so the pan is only partially full, while other brands top up the pour a second or third time for a fuller pan. And of course the actual formula of the paint differs, with some paints adding some honey, some having different amounts of gum arabic binder, some adding wetting/flow agents and some not. Some with honey are not as soft because they are extruded, while the poured honey paints can be only semi-hard. These differences in formula are more readily visible in a pan than a tube, as a shiny/matt, sticky/smooth, or soft/hard surface.

Tubes
Most brands of watercolour make two sizes of tubes, their small and their large. The most common sizes are 5ml, 10ml, 14ml, 15ml, or 21ml. In addition to their two regular sizes, Winsor & Newton also do a very large 37ml tube. Some of the brands that only do one size of tube often do it in an unusual size such as 7ml, 9ml, 11ml, and 24ml.

Occasionally you may find a favourite paint and not have a choice of format. There are some brands that are only available in one format – some that only come in tubes and some that only come in pans.

Read an excellent article to compare the benefits of watercolour paint in pans versus tubes here

Watercolour Sticks
Sticks are dried watercolour in stick form. They can be used like pans, i.e. by wetting the brush to extract the colour from the stick, and they can also be used as a drawing tool by applying colour from the stick straight onto paper, either wet or dry. Watercolour sticks are highly pigmented and lightfast. Their special formulation means that they can be used dry and then can be wetted, after any length of time, for maximum convenience. Simply add water to turn a drawing into a watercolour even years after it was completed.

Watercolour sticks can be used to add details to existing watercolour artworks. The unique square shape is great for achieving multiple line thicknesses, and they are also intermixable with other watercolour paints. They are perfect for in the studio or outdoors on the go.

Watercolour Pencils
Watercolour pencils are convenient and portable little painting tools that are clean and easy to use. Their versatility means you can use a single pencil with many different techniques. 

They usually contain some wax to keep the lead solid and can be used on their own or with traditional watercolour paint. They can be used dry as regular coloured pencils, or like pans (extracting colour using a wet brush), or they can be dipped into water and drawn with, creating intensely saturated marks.

What mediums can I use with watercolour?

Watercolour mediums, although not essential, can help you control how watercolour paint behaves. You can use them to add texture, improve flow, make it easier to lift colour, and alter the drying time.

Gum Arabic
Gum arabic is used to bind pigment in watercolour manufacturing processes, and is made of hardened sap extracted from two species of the Acacia tree. It is sometimes known as chaar gund, char goond, or meska. Gum arabic dissolves very easily in water, and is used as the binder in watercolour because it also effectively binds the pigment to the paper surface once the water has evaporated, and it can be rewetted, it does not dry water-resistant. It allows for more precise control over watercolour washes as it limits the amount of flow and/or bleed of the colour. Gum arabic also slows the evaporation rate of water, which means that it keeps your watercolour wet for longer, allowing for longer working times. Once water has evaporated from watercolour, the colour’s luminosity and transparency, as well as permanence, is enhanced by the gum arabic. 

Gum Arabic is sold separately for those who wish to try making their own watercolour paints by combining it with dry pigment, and it can also be used as a medium to mix in with pre-mixed colour, to further optimise transparency, luminosity, and and adds gloss.

Sennelier Watercolour Binding Medium
Sennelier Watercolour Binding Medium replicates the recipe used by Sennelier in the manufacture of their own range of watercolour paint. It is made of gum arabic, honey, water, and a preservative. This recipe optimises gloss and luminosity of colour as well as providing a lustrous consistency and a stable structure that will optimise the permanence and stability of the paint structure. Sennelier binding medium can also be used as a flow aid or thinning medium during the painting process with ready made colour, optimising transparency and colour brilliance.

Masking Fluid
Watch our How to Apply Masking Fluid video on YouTube.

Traditionally, in watercolour painting, the whites are not added as paint but are reserved areas of the paper that are not painted on. Masking fluid is a liquid latex-based product that is very effective at keeping small areas and thin lines white when painting on watercolour paper. Once dry, applied masking fluid will prevent the paint from reaching the paper and can be peeled off to expose the white paper once the painting is fully dry. The areas where masking is most useful are small white areas or lines within a large even wash of colour, like sailboat rigging against the sky, where you don’t want to paint around areas and interrupt a smooth wash.

The masking fluid can be applied in many ways, almost any tool will work. If you need splattered white dots you can flick the masking fluid from an old toothbrush. You could use a brush, a ruling pen, a dental pick, a Colourshaper applicator or a special Masquepen or Super Nib which is a needle that gives extremely fine lines. The Super Nib comes with an empty squeezy plastic bottle, which you can fill with water, attach the nib to, and then squeeze the water through in order to rinse the nib. The sooner you do this after using the Super Nib, the easier the cleaning process will be.

If you're using a brush for applying masking fluid, it is advisable to allocate an inexpensive brush to this purpose, as it is very easy for masking fluid to dry and become ingrained in the brush hairs. One trick to make it easier to clean your brush is to wet the brush thoroughly and wipe the hairs over a bar of soap or dip it into washing up liquid, making sure that the hairs are thoroughly coated right up to the ferrule before using it to apply the masking fluid. Wash the brush thoroughly immediately after use.

Masking fluid is available clear or tinted, so you can see where you have painted it.

How to Apply Masking Fluid
The paper must be dry when you apply the masking fluid. If it is wet, the masking fluid will soak deeply into the paper rather than sit on its surface, and it is likely to tear the paper when it is eventually lifted away from the paper after use. The same problem may occur if you dilute the masking fluid with water prior to use. Additionally, look out for air bubbles - these are easily created if the bottle is shaken, and if they are applied to your work the bubbles may pop while the fluid is drying and leave unmasked spots.

Wait until the masking fluid is completely dry, at least five minutes, before you apply your watercolour. After you have finished your painting and it is completely dry you can then remove the masking fluid. Some artists rub the edge of the dry masking fluid with their finger or a putty rubber to coax it away from the surface of the paper. Dried masking fluid is very elastic and lifting should be done slowly and carefully to avoid any risk of tearing your paper.

Remove the masking fluid as soon as possible after the painting is dry. The longer the mask is left on the paper the harder it will be to remove it. Additionally, tinted masking fluid can stain your paper if it is left on the paper for a long time.

Once you have mastered using masking fluid you will be rewarded with those lovely sparkling whites in your watercolour paintings, and it may soon become a tool that you use regularly in your work.

Watercolour mediums

Granulation Medium
When granulation medium is mixed with watercolour paint it gives it a mottled appearance when the colour would normally appear as a smooth wash. Some colours naturally do have a mottled or granulated appearance, such as French Ultramarine. Granulation medium would serve the purpose of increasing this characteristic in such pigments.

Schmincke Aqua Gloss
Schmincke Aqua Gloss remains watersoluble, and can be applied on to dry watercolour to enhance its gloss, or mixed in with wet watercolour as a medium. It also slows the drying time. It is advised not to mix aqua gloss in a watercolour pan as it may affect the paint for future use.

Iridescent Mediums
Aqua Shine and Iridescent medium are both pearlescent watercolour mediums that add a shimmer effect to your colours. Both Aqua Shine and Iridescent Medium retard drying and stay watersoluble.

Ox Gall
Ox Gall for watercolour is made of the gall from cows mixed with alcohol. It is a wetting agent that increases the flow of the paint across the paper. It is added to many watercolour paints. Some paints do not contain a wetting agent because they want a more controllable paint. Some paints use a synthetic ox gall to avoid animal products. You can purchase it separately to add to your paints.

Winsor & Newton Blending Medium
Winsor & Newton Blending Medium slows the drying time of watercolours which enables a longer amount of time for blending. Winsor and Newton Blending Medium is therefore particularly useful when painting in a hot climate.

For Experimental Watercolour Techniques:

Schmincke Aqua Collage
Schmincke Aqua Collage is formulated for artists who wish to use watercolour in mixed media works. Aqua Collage dries water-resistant. It is an adhesive that can be applied on its own (in which case it will dry clear and invisible), or it can be tinted with watercolour. You may wish to use it to glue photos or coloured paper to your watercolour paper, and then work over the top once dry. When dry aqua collage can be painted over without resisting the paint in the way that PVA glue might.

Schmincke Aqua Effect Spray
Schmincke’s Aqua Effect Spray is for the very experimental watercolour painter! Spray into wet watercolour work to create what Schmincke refer to as ‘bizarre surface effects’ on watercolour paintings – it causes the pigment to gather up into pools, to create effects similar to flocculation or marbling - an undulating surface consisting of passages of both saturated and very dilute colour. It is worth trying it out on a separate piece of paper to fully understand what effect it might have on your work. Because Schmincke Aqua Effect spray is in a pump spray bottle, be sure to mask off any areas that you do not wish to apply the effect to.

Schmincke Aqua Pasto
Schmincke Aqua Pasto watercolour medium is manufactured by both Schmincke and Winsor & Newton. This medium potentially bridges the gap between watercolour painting and the impasto techniques you’d be more familiar with in oils or acrylics, and really does add another dimension to the process of watercolour painting. This transparent thickening medium can be applied pure onto paper, or mixed with colour prior to application, and creates a paste-like texture. You can even start to apply your watercolour paint with a spatula! Aqua Pasto reduces flow and increases gloss. It slows the drying time and stays watersoluble, so can be re-worked over time. 

Schmincke Aqua-Fix
Schmincke Aqua-Fix is a medium that increases the water resistance of watercolour. It allows you to avoid dissolving the colour when painting in several layers and creates more possibilities for transparent painting. Be aware that if you mix it with the paint in the pan the paint will harden and be ruined, so the idea is to use the Aqua-Fix instead of water on your brush and palette. It makes it a bit more like acrylic.

Watercolour Surface Preparation
Watercolour primers and grounds can be applied to  a variety of materials including canvas, wood, stone, ceramic, and plastic to create a surface that is absorbent enough to hold applications of watercolour and optimise the appearance of colours and marks. Three thin, even layers that have been allowed to dry fully in between the application of each layer will optimise absorbency and allow you to achieve the same watercolour effects possible on regular watercolour paper. Watercolour primers and grounds are made by a number of paint manufacturers including Schmincke, Daniel Smith and Golden Paints, and are available clear as well as in a number of different shades. There are also coarse and fine tooth varieties available.

How easy is it to clean up my workspace after watercolour painting?

As a watersoluble medium, watercolours are very easy to clean! Paints will wipe away from most surfaces using soap and water, while clothing stained with watercolour paint can also be easily hand or machine washed without any additional treatment.

Brushes for watercolour

Brushes for watercolour painting have shorter handles than oil and acrylic brushes and are available in a variety of shapes. Small brushes are useful when painting detail and other intricate marks while large brushes will hold more liquid and work well for broader brush strokes and washes. Traditionally, sable hair is often used because it holds a lot of liquid, but today there are plenty of synthetic alternatives, as well as brushes that have a blend of natural and synthetic hair (this article shows a comparison between sable and synthetic sable brushes). 

For a watercolour beginner, a brush set with a variety of shapes and sizes is a great way to get started. As you paint more you will begin to discover which brushes are your favourites. You can then build on your collection of watercolour brushes with the right shapes and sizes for your way of working. Starting with a set of at least three brushes is ideal. The highest quality natural hair brushes (such as sable or squirrel) are the most expensive, while synthetic brushes offer a hardwearing alternative. 

To read more about watercolour brushes, have a look at our Guide to Watercolour Brushes here.

To read more about how brushes for watercolour are made, read A Family Matter: Handcrafting Brushes

Care and cleaning of brushes

The lifespan of your brushes will be prolonged if they are kept clean and cared for. Both natural hair and synthetic hair brushes benefit from being cleaned with brush soap as it contains natural oils which help to moisturise the hairs, so they keep their strength and shape. If the hairs are not sufficiently moisturised with oils, the structure of each filament becomes brittle, and the hair is more susceptible to breaking, or splaying, damaging the shape of the head of the brush. Therefore it is a very good idea to get into the habit of doing the following at the end of each painting session:

1. Remove the excess paint from your brush. Rinse in a jar of cleaning water or under a running tap and then blot on a clean rag or kitchen towel. 

2. Gently rub the head of the brush on to your brush soap. Work into a lather with your fingers. 

3. Rinse under running lukewarm water and repeat until the lather remains white. Remember to work the lather with your fingers right up against the ferrule.

4. Once the hairs are clean, blot on to another clean rag and shape the brush head with your fingers.

5. Leave to air dry, ideally by hanging the brush from its handle somewhere reasonably well ventilated. This will allow any water in the ferrule to leave the brush, preventing any rotting of the handle to occur.

Tools for watercolour painting

Palettes
An extra palette will offer more room for colour mixing, on top of the palette area offered in most watercolour paint boxes. If you’re going to want your colour mixes on another day, or if you need to transport your colours, a palette with a lid will protect your mixed paint as well as offer even more palette space. All watercolour palettes have at least some wells – these are for squeezing tubes of colour out into and ensuring that the colours do not run into one another. Palettes are offered in plastic and ceramic.

As an aside, watercolour paints do have a tendency to bead up (gather in pools and possess a resistance to the surface) on new or plastic surfaces. However this effect wears away the more you use the palette for colour mixing. Lightly scrubbing the palette with a brillo pad prior to use, and rinsing thoroughly to remove any traces of soap, will stop the beading. Alternatively you can invest in a porcelain palette on which watercolour paints do not bead.

Pencils
Often, a set of artist pencils are worth having with your watercolour painting equipment as preparatory sketches can help to develop your ideas before you set brush to paper, allowing you to have more confidence during the painting process. A hard pencil can be useful in lightly drawing your composition on your paper before you apply colour. Graphite or coloured pencils won’t smudge, but it might be best to avoid charcoal pencils for this reason.

Easel
An easel is by no means essential. If you work standing up you could tape your watercolour paper to a wall, or you could work at a table. However, the right easel could allow you to move your work easily to better lighting conditions, or help you to work with a healthy posture, avoiding unnecessary aches and pains during a long painting session. When choosing an easel you have to ask yourself a set of questions:

Will you be painting at a table? If you will be, then a table easel is a compact device that will hold your paper upright. Many have a drawer in which you can store your paints and brushes. They are easy to store.

Will you need to have a portable easel (perhaps for painting out of doors)? If you will be, then a sketching easel is what you’ll need. Sketching easels are usually made from aluminium or wood. An easy to carry sketching easel will be lightweight with telescopic legs allowing it to fold into a compact portable size. However if you are likely to paint in bracing wind conditions it may be at risk from falling over. Some string and tent pegs can be a great way to get around this.

Do you need an easel that will tilt to horizontal? (will you be painting with lots of dilute watercolour which might run?) Some studio and sketching easels will tilt fully to a horizontal working position, which can be really useful if you need to ensure your paint does not run.

Do you need an easel that will hold very large work? The largest studio easels are H-frame and solidly stable for paintings up to 235cm, but they will take up space and be heavy to move around. Crank handle easels make it easier to adjust the height of your painting.

Sponge
A sponge can be used to lift wet colour from a painting, to either reduce the colour saturation of the brush mark, to lighten its tone, or to remove it completely. Watercolour is rewettable, so applying clean water to a passage of painting will allow you to remove some of the paint if you then dab the area with a clean sponge. A sponge is also useful for blotting a loaded brush (to reduce how much paint will be deposited with your brush mark), and also if you get into stretching your own paper, it can be really useful for removing excess water from the gumstripped edges of your paper.

Pots
You will need a pot of water in which to rinse brushes when changing colours, or at the end of a session. While a glass jar is perfectly usable at home, you might like to reduce the weight of your load if going elsewhere to paint. There are a number of collapsible water pots available that fold compactly back into your kit bag at the end of your painting session.

What is the best surface for watercolour painting?

Watercolour paper is a versatile surface which has a degree of absorbency that allows transparent colour to appear its most luminous. Watercolour paper is not only for use with watercolour paints – it can also be used for acrylics, gouache, pastels, pencils, graphite, charcoal, and it can also be primed for oil. With many 100% cotton papers available, it can make a durable and archival support for many different mediums. 

Watercolour paper is usually available in three different textures. Completely smooth paper is known as Hot Pressed and allows for the finest lines and crisp details to show. Cold Pressed paper has a slight texture and is also known as NOT surface paper. It is the surface that most artists try to begin with. The texture is made with sheets of felt, so has an irregular, naturally dimpled quality. Rough paper has a more pronounced texture, which acutely changes the quality of brush strokes, often making them appear more broken and expressive than on smooth paper.

Hot pressed paper has the least textured surface, having been pressed between hot metal rollers during production. Hot pressed paper is favoured by those who like to work delicately with a lot of detail, such as botanical artists. Hot pressed paper tends to be the least absorbent of all of the textures, and watery washes can sit on the surface for a long time. Beyond watercolour painting, hot pressed watercolour paper makes an excellent support for detailed pen, ink, and graphite drawing.

Cold pressed (NOT) paper is made by pressing the sheet through cold metal rollers and it has a slight texture to it. It is the most popular watercolour paper surface to work on because it is well adapted to many painting approaches. The paint will sink a little into the dimples on the surface of the paper, but it will also be sympathetic to more detailed work. Cold pressed paper tends to be a little more absorbent than hot pressed paper.

Rough paper is the roughest texture paper available. It is pressed between sheets of textured felt during the drying process and is not pressed between smooth rollers. The heavier texture means that granulating effects are enhanced. This paper surface is suited to bold, expressive painting techniques.

While hot pressed, NOT, and rough are used almost universally by watercolour paper manufacturers to describe the texture of their papers, the actual surface textures vary greatly between manufacturers, or even between batches (particularly with handmade papers).

Watercolour pads and blocks
A watercolour pad is bound on one edge and is ideal for sketches. Watercolour pads are either spiral or glue bound, and would be a good source of paper for a beginner. Another option would be watercolour blocks, which are glued on all four sides, which keeps the paper taut as you paint on it. When your painting is finished and dry, simply slice off the top sheet by running a dull knife all around under the sheet, and your painting will be on a flat piece of paper, free from natural buckling caused by water saturation. If you want to paint large, then you may wish to work on full sheets of imperial watercolour paper, which measure 22 x 30 inches. If you want to try painting in watercolour on an even bigger scale, then a watercolour paper roll might be what you’re after. Most are 10 metres long, which you can cut down to whatever size you need. To read more about the sizes and formats of paper click here.

Watercolour Paper Comparison Table
Our table compares the fibre content, texture, sizing, colour, and surface strength of artist watercolour papers. Click the image below to enlarge, or download our PDF version here to print.

Why Does Paper Buckle When Wet?
Buckling occurs because paper fibres expand when wet. If you use very little water in your technique then very little buckling will occur, if any. For more watery applications, a heavier weight paper (425gsm and above) will buckle less.

Stretching watercolour paper involves deliberately saturating the paper with water in order to expand it prior to fixing it to a board, usually with gumstrip around the edges, then allowing it to dry and shrink back before painting. Preparing your paper like this ensures a completely flat surface.

How to Stretch Watercolour Paper: A step-by-step guide

What you will need:

A clean, soap-free tray of water, with one dimension slightly longer than the shortest edge of your sheet of paper or, if you don’t have a tray, a clean spray bottle.
A clean, soap-free sponge or paper towel.
A rigid board – plywood or plastic is ideal.
4 strips of gummed tape, to glue each edge of your paper to the board. It helps to pre-cut each length so that it is 3cm longer than each edge.

The most common and inexpensive method of stretching paper is to begin by soaking it in clean water for a few minutes (140lb weight paper will need up to 8 minutes, heavier paper may need more). If your sheet of paper does not fit in the tray you can hold it at opposite edges and feed it through the tray multiple times to ensure the whole sheet is soaked.

Lift the sheet from the tray and allow any excess water to drain from it before placing it flat on your board. If you do not have a tray simply place your paper on to the board you wish to stretch it on to, and spray generously on both sides of the paper with clean water. Try to only touch the paper on its edges as it’s possible to leave visible finger marks. Sponge off the excess water gently with a clean sponge – the outward motion you use to do this will help flatten the paper onto the board. Once you feel that the paper is adequately stretched out, wet your gumstrip using a clean paintbrush or sponge, but do not immerse it in the tray of water for too long as this can wash away too much of the adhesive, and it may not be able to hold the paper in place as it shrinks.

Place the gumstrip tape on the edges of the paper so that half the width is covering the paper’s edge, and half is stuck to the board. When doing this, take care not to let water from the tape drip onto the paper, as this will leave spots on the paper when you start to paint on it. Use a dry paper towel to press the tape down, which will also soak up any excess water. Lay the board flat and allow it to dry (it may need to be left for a few hours, or overnight to be completely dry) before you start your painting.

When your painting is finished, leave it to dry completely before cutting the paper free from the board using a sharp craft knife. You can remove gumstrip from the paper by soaking it with a sponge to rewet it, and then carefully lift it off with a palette knife or craft knife.

How do I present and store finished work?

Historically, watercolour paintings have been displayed framed behind glass because they are on paper which can be stained by dirt and dust, can’t be cleaned with water and wrinkles with humidity. In addition, the watercolour paint itself is vulnerable to being re-dissolved with water. What if you wanted to paint a watercolour on a surface other than paper, one that is less sensitive to water like canvas – is there a way to make the watercolour paint permanent so it can be framed without glazing like an oil painting?

To clarify, it is not necessary to varnish a watercolour painting and varnishing is not usually done for traditional watercolour paintings. But there has been some interest in varnishing watercolour paintings because some artists would like to paint on canvas or mount the paper on wooden panels and want to show their paintings without glass, and they like the different look of a watercolour that has been varnished.

For an in-depth look at watercolour varnish, read the article Watercolour Varnish: Can You Make Watercolour Waterproof?

Glassine – for protecting work in storage

Glassine is a glossy greaseproof paper that is designed to protect artworks from smudging. Loose sheets of glassine can be purchased in packs or singularly and are useful to keep in supply. The loose sheets are ideal for interleaving between stored works.

Glass – for protecting and presenting finished works

Arguably the most secure way to protect a watercolour painting (and works on paper in general) is by framing the work behind glass, although of course this is also likely to be the most space consuming solution as well. As with all work on paper, it is best to have a gap between the work and the glass to allow any humidity to circulate away from the work and prevent any shifts in the position of the glass smudging the work. A window mount offers a good solution to this, or alternatively the use of spacers in your frame.

Glossary

Mass Tone - The appearance of the colour of the paint as it comes from the tube.

Undertone - Undertone is the colour you see when the paint is in a thin, diluted layer. For example many yellows are dark brown in masstone but when diluted and painted thinly are bright, light yellows.

Colour Strength - Colour strength refers to the concentration of pigment in the paint. Also called the pigment load.

Opacity/Transparency - Is the measure of how much light is able to pass through the pigment particles. Opaque colours allow only very small quantities of light through the colour whereas transparent colours allow a lot of light through the colour. The difference is that opaque colours will look flatter and will cover over any marks that may have been made underneath. Transparent colours will show the marks made underneath, and may appear to have more texture.

Traditionally watercolour painting is a transparent painting method and conventionally it is the white of the paper being painted on that acts as the white in your work, however it is now common practice for many watercolour painters to use white gouache or Chinese white watercolour in a watercolour painting, often as finishing highlights and touches. White gouache can be tinted with transparent watercolour and used in watercolour painting; it is often referred to as ‘body colour’ due to its opacity. Blending the fusing of 2 colour planes with one another in such a way that there are no hard edges. In watercolour this is easily done with a wet brush, dipped in either water or gum arabic. If watercolour is allowed to thoroughly dry then blending is made a little more difficult – the edges may be harder to lift. In instances such as this, a blending medium can be mixed with the colour to prolong the amount of time that the colour is wet, and make blending a lot easier.

Dry Brush Technique - When watercolour paint that is relatively dry, and in the least ‘gummy’, is applied with a dry brush to paper. The effect is chalky in appearance, and saturated in colour, and often makes for a dramatic contrast against more delicate, watery, watercolour washes. A very effective and dramatic method for creating textured surfaces within water colour painting.

Watercolour Easels - Watercolour easels often tilt to allow painters to work flat (preventing washes and large amounts of water from running). However some watercolourists may find that working upright works for their preferred technique.

Flat Wash - The use of a single diluted colour to cover the white of the paper in a relatively unsaturated and uniform manner. Washes are usually applied with a broad brush with natural hair that can hold a lot of fluid, such as a squirrel mop. Painters may choose to work over the wash once the wash is dry, or to work into the wet wash. By doing this one is said to be painting ‘wet on wet’ and the result is that the colours bleed into the layers onto which they have been applied. Flat washes can be applied on to dry or damp paper.

Fugitive Colour - Refers to non-lightfast paints, such as Opera Rose. They fade, or distort in other ways, when exposed to sunlight. Generally it is advised to stick to colours that have been rated of excellent or very good lightfastness (they may also have the classification of being ‘I’ or ‘II’) if you are intending on exhibiting or displaying work on a wall, as opposed to keeping it in a book or portfolio.

Glazed Wash - A glazed wash is when a dilute colour is applied across the surface of a watercolour painting that has been left to dry completely – the result of doing this is to tint the whole surface with the colour of your wash. Someone who decides to apply a glazed wash over a work would therefore have to consider the influence the chosen glaze hue would have over the colours that have been worked with previously. Once dry the artist has the option to work over the top once more.