How To Grow Wallflowers

What is a wallflower?

Wallflower flowers are often highly fragrant and come in an array of colours including yellow, red, orange and pink. They’ll grow to a height of between 20-40 cm – making them a perfect choice for garden borders and container displays. 

They are biennial plants (meaning they take 2 years to complete their biological lifecycle) that need to be grown freshly each year. However, this is not necessarily a fixed time scale, knowing how to grow wallflowers and using best practice, your bushy plant may become perennial, surviving over successive seasons. 

The best time to plant wallflowers

Autumn bedding makes for a vibrant, full-bodied display in the spring. We recommend that you plant out your plug plants from late August – mid-September, depending on the size of the plants acquired. 

How and where to plant wallflowers

Ideally, you should grow wallflowers indoors until they reach 8-10 cm in height, at which point they’re ready to plant out. The ground should be prepared before planting out. Dig it over thoroughly, and mix in plenty of organic matter – such as manure or leaf mould. The planting location should have good drainage and ideally, the soil should be slightly alkaline.

For planting in beds or borders, use a trowel to dig an individual hole for each plant deep enough to submerge the root ball, while also keeping the base of the stem at soil level. Position the plant and fill the hole back in. Gently firm down and water in.

Wallflower planting distance is important; you must position plants at least 15cm from each other to allow them room to flourish.

When do wallflowers flower?

Different varieties of wallflowers flower at different times. However, February to May and May to June are the peak months where wallflowers tend to be at their best. To encourage the plant to become more bushy, giving a more intense display of colour, we recommend that you pinch back the growing tips once the plant is established.

By pinching back, you force the plant to grow twice as many stems, which results in a fuller wallflower display. Simply pinch the stem above the leaf nodes using your fingers as shown in the diagram above, or using pruning shears.

Wallflowers plant care

Wallflowers are hardy and tough, though prolonged frost may weaken the plants. After a frosty night, you may notice drooping leaves on your plants – particularly if it is windy. Fear not, this is a reaction to the weather conditions, plants will perk back up and remain healthy once the weather has settled. 

Longer-term drooping or wilting may be due to diseased roots, in which case the plant should be removed, or to a bacterial infection on the leaves – check for any signs of this and remove affected plants.

Not sure what to look out for? Here are 5 of the worst garden plant diseases and how to treat them.

Ready to grow your very own wallflower display now you know how to grow wallflowers? Take a look at our wallflower collection.