As part of the watercolour course I teach I like to show students how to tackle difficult subjects. One of those is how to deal with white when painting with watercolour.
I encourage students not to draw out in pencil. This isn’t because I have a problem with pencil, but because once a graphite line is in students tend to treat it as gospel and be unwilling to rub out. The first step is to make a quick sketch on rough paper or your sketchbook. Use this as a guide for composition and tone.
Then, using a neutral, light coloured watercolour pencil draw your rose outline.
Once the outline is in (don’t use a rubber if you make a mistake, blot out with water and kitsch roll) then start putting in your base colours. The easiest way to make the rose look whiter is to darken the background.
Keep building up the colours to desired intensity. I use a cotton bud to blend without too much pigment on the pedals. Simply dip one end in clean water, blend your paint from darkest part if pedal and use the dry end to smooth out the colour.
A different approach would be to use masking film or masking fluid. This keeps the white of the paper allowing you to paint around it and remove at the end.
If you’re interested in finding out more watercolour techniques I’m teaching a one day “Introduction to Watercolour Painting” course at Merton Adult Education, Thursday 16 July 2015. Starting at 9:30 and running until 15:30 with lunch and tea breaks. The course is just £23. For more information see MAE’s website.