Clumber Gardener: Wonderful Wallflowers

Scented plants bring extra interest and pleasure to a garden. By careful selection, shrubs, perennials, bulbs and annuals can provide perfume throughout the whole year.
Wonderful Wallflowers: Clumber GardenerWonderful Wallflowers: Clumber Gardener
Wonderful Wallflowers: Clumber Gardener

This month hyacinths, viburnums and, especially, wallflowers, with their bright red, orange and yellow flowers, come to the fore. Their perfume can be sublime after a spring shower on a sunny evening.

Varieties are available as individual colours or mixtures and height varies between 8ins/20cm and 24ins/60cm. ‘Tom Thumb’ (height 8ins/20cm) and ‘Persian Carpet’ (height 14ins/35cm) usually come in mixtures including red, orange and yellow, whereas the ‘Bedder’ series has single colours, including scarlet and primrose.

‘Vulcan’, as the name implies, has velvety deep red flowers. Height is around 12ins/30cm. Combined with forget-me-nots, pansies and tulips, particularly the taller stemmed varieties which will display their flowers above the other plants, bedding wallflowers can produce exuberant, colourful planting schemes to brighten our spring garden.

Wonderful Wallflowers: Clumber GardenerWonderful Wallflowers: Clumber Gardener
Wonderful Wallflowers: Clumber Gardener

The latest advance in wallflower breeding is F1 hybrid wallflowers, which like all other F1 hybrid plants, are uniform and vigorous. The ‘Sunset F1’ series is available in individual colours and mixtures, height is 10 to 12ins/25 to 30cm. The downside for gardeners is that F1 hybrid seed is expensive, for example 20 to 25 seeds of a ‘Sunset’ variety will cost between £2.32 and £3.69, whereas 500 seeds of the ‘Bedder’ series will cost around £1.20.

Traditionally, garden centres and nurseries have sold bare root wallflower plants in September and October. If you have the space, growing from seed is comparatively easy.

Towards the end of the month and throughout June wallflower seed can be sown in a prepared bed. Wallflowers belong to the same family as cabbages, cauliflowers and sprouts, so avoid an area that has grown these and other brassicas recently. Sow in shallow drills about 1/2ins/1cm deep. When seedlings are about 4ins/10cm tall, carefully lift them and plant in rows 4ins/10cm apart Weed and water as necessary.

Transplant plants to their spring display area in October. If you’re combining them with tulips, bulbs can be planted at the same time. Plant firmly. Well grown stocky plants with lots of side shoots will provide the best display. Sheltered, sunny spots on free draining neutral to slightly alkaline soil give the best results.

Although we treat bedding wallflowers as biennials, they are short lived perennials and a few other varieties are grown like this and make excellent plants in rock gardens, mixed borders or containers. In the catalogues you may find them listed under their botanical names, Cheiranthus or Erysimum. ‘Bowles’ Mauve’ grows to about 30ins/75cm has grey blue leaves and mauve flowers which are produced from late winter to summer. ‘Harpur Crewe’ has double yellow double flowers and a strong aniseed scent. There are also variegated leaved wallflowers which make good container plants. Erysimum linifolia ‘Variegata’ has attractive cream margins to its foliage and long lasting mauve flowers in late spring and early summer. As they are short-lived perennials, they are best propagated regularly from semi-ripe cuttings taken in late spring or summer.

Jobs for the Month – May

For many of us May is the busiest month of the year. Plants and weeds are growing apace, containers need watering and there is lots of sowing and planting to do.

Plant out tender and half hardy bedding plants towards the end of the month. Make sure you catch the latest weather forecasts and if frosts are forecast, protect tender plants with horticultural fleece.

As soil temperatures rise, weed seeds germinate. Keep these under control by hoeing them off on dry, sunny days.

Watch out for pests and diseases. Slugs and snails were a major problem in last year’s wet summer.

Water young vegetable transplants if the weather is dry. Thoroughly water around the base of the seedling, rather than superficially wetting the soil surface. Mornings or evenings are the best times to water.

It’s busy, but don’t forget to enjoy your garden and visit other gardens, especially those noted for their displays of rhododendrons, azaleas, camellias, alpines and spring bulbs. Many gardens also stage events this month. In Clumber Park’s Walled Kitchen Garden there is a rhubarb weekend on 11th and 12th May. For more information, go to www.nationaltrust.org.uk/clumber-park/