Viola: Following These Care Guidelines Will Prolong Their Long Flowering Season
Reviewed By COLIN SKELLY
Colin is a Horticulturist and Horticultural Consultant with experience in a range of practical and managerial roles across heritage, commercial and public horticulture. He holds the Royal Horticultural Society’s Master of Horticulture award and has a particular interest in horticultural ecology and naturalistic planting for habitat and climate resilience.
All too often pigeonholed, violas are among the most versatile flowering plants, they are easy to grow and have long flowering seasons.
These colourful little blooms are possibly the cutest and cheeriest yet gentlest and most laid-back flowers you can grow just about anywhere in your garden, be it in a bed of their own, around a tree, or in a little corner.
In this guide, we will tell you everything you need to know about growing and caring for violas growing in your home and garden.
Overview
| Botanical Name | Viola spp. |
| Common Name(s) | Viola / Violet / Pansy |
| Plant Type | Annual or Perennial |
| Native Area | North America and Europe |
| Hardiness Rating | H7 (depends on variety) |
| Foliage | Evergreen |
| Flowers | Small flowers of lots of different colours |
| When To Plant | May-August |
| When To Prune | May-July |
Sunlight
Preferred
Full Sun or Partial Shade
Exposure
Exposed or Sheltered
Size
Height
0.1 – 0.5M
Spread
0.1 – 0.5M
Bloom Time
Depends on variety
Soil
Preferred
Most fertile soils
Moisture
Moist but well-drained
pH
Acidic to neutral
Viola tricolor is a herbaceous plant that has rhizomatous roots and grows to 15-25cm in height.
It bears a small flower of about 2.5cm that has five petals.
It is coloured purple, yellow, and white with dark streaks.
These plants are annuals, biennials or short-lived perennials in the wild.
Many of their numerous cultivars are evergreens in temperate climates but are all too often seen and treated as annuals.
Viola flowers are relatively gentle, laid-back charmers that have been overshadowed over the past several decades by their bigger and bolder siblings – pansies.
Varieties
Here are some of the most common viola varieties that are grown in the UK.
All of the following varieties are hardy to H5 or H6.
- V. ‘Carousel’
- V. ‘Bridie’
- V. ‘Clementina’
- V. Vibrante Series
- V. Sorbet Series
- V. ‘Yellow Blue Jump Up’
- V. ‘Magnifico’
- V. ‘Rose Shades’
- V. ‘Bambini Mixed’
- V. ‘Penny Peach Jump Up’
- V. × williamsiana ‘Floral Power’
Where To Plant
Though Violas are commonly used for borders and edging, a good mix of violas can fill a bed on their own.
Violas are also great plants to intersperse amidst taller ones that bear bell-shaped or trumpet-shaped flowers such as daffodils, amaryllis, daylilies, and bluebells.
In view of violas’ profiles and habits, they are very well suited for rockeries.
Of course, they make the very best potted plants to put on the porch or the patio, or in a window box.
Finally, violas have a secret strength: they make delightful indoor plants!
Choose the right variety and you can keep a small pot or container of violas on a tabletop or the kitchen window where they will get morning sun.
“I also grow violas in the vegetable garden and in the greenhouse as food for the stomach as well as the soul,” shares Horticultural Consultant Colin Skelly.
“Violas are increasingly popular as a colourful and edible garnish for salads and regular harvesting keeps them flowering for longer.”
Growing Requirements
Soil
Any type of loamy soil works for violas but the best soil for them is a rich, fertile, slightly acidic soil.
Amending your garden soil with about 25% peat-free moss and organic compost will do wonders for your violas.
They need free-draining acidic soil and will not do well in alkaline conditions.
Light
Violas in most regions of the United Kingdom will do best in full sun.
Some varieties, like their sibling pansies, will succumb to the summer sun in the warmer regions of the country and these should be grown in part shade.
In any case, almost all violas will perform well in a partially shaded site.
Planting Viola
When and for how long a viola variety will flower depends on the season in which the seeds are sown.
Though the sowing season often determines when violas flower, the prime seasons to sow them are sometime in spring and in late summer to early autumn.
As a general rule, sow seeds in spring for the plants to flower in autumn, and vice versa.
Ongoing Plant Care
Watering & Fertilising
Evergreen violas that flower through the summer will need more water during hot weather.
You do not need to fertilise violas if you have amended the soil with garden compost.
Otherwise, and for evergreen varieties in their second year, fertilise them in spring and autumn.
You can use slow-release granules or a liquid fertiliser.
Pruning
The more you deadhead violas, the more profusely they will flower.
However, if you would like your violas to self-seed so that you keep getting new plants, allow a good number of flowers to die and go to seed.
Common Pests & Diseases
Violas that are grown outdoors or indoors are susceptible to powdery mildew, downy mildew, pansy leaf spot, and other fungal diseases.
You can minimise the chances that your violas will contract a fungal disease by watering them at the soil level so that the foliage does not get wet.
Violas might also be attacked by aphids.
If slugs or snails are found in your garden or its vicinity, they will almost surely go for your violas, so be prepared for them.