How to grow and care for wallflowers
How to grow wallflowers
Cultivation
Bedding wallflowers prefer to be grown in full sun but will tolerate light or dappled shade.
For best result they prefer a fertile soil enriched with lots of organic matter which holds plenty of moisture in spring and summer and doesn’t dry out or become waterlogged. However, they will tolerate poor soils. Add a general or high potash granular feed to the soil before planting out.
Perennial wallflowers need full sun and prefer poor to moderately fertile, well-drained, neutral or, preferably alkaline soil.
Sowing bedding wallflowers
Wallflower seeds are sown from May to July.
You can sow the seed directly outside in the ground. Choose a sunny position with good, well-drained soil. Sow thinly at a depth of 13mm (0.5in) deep in rows 30cm (12in) apart. Cover the seed with fine soil and water in well. Water regularly, especially during dry periods. When the plants are large enough to handle you can transplant them to their final flowering positions.
It is usually better to sow wallflowers indoors in seed trays, cell trays or pots of good seed sowing compost at a temperature of around 13-15C (55-65F). Put the container inside a polythene bag or propagator. When seedlings are large enough to handle, transplant them individually into pots and grow them on in cooler conditions before planting outdoors in their final flowering positions.
When the young wallflower plants are 12.5cm (5in) tall pinch out the growing point to make them bush out.
Planting wallflowers
For bold, colourful bedding displays plant out around 30cm (12in) apart. The best time to plant out bedding wallflowers is in September or October.
If you don’t grow your own from seed then plug plants and seedlings are available from mail order seed companies and larger, ready-to-plant plants are available from garden centres. Traditionally these are available as bare root having been dug up out of the ground. Make sure the roots are given a good soaking in a bucket of water for 20-30 minutes before planting.
The perennial wallflowers like Bowles Mauve can be planted any time of year but the best time is during spring.