Buddleia ‘Joan’

Buddleia 'Joan' (Buddleja davidii 'Joan') is the shrub to plant if you want butterflies in the garden by the end of the first summer. It reaches about 2.5m tall and 2m wide, grows fast enough to fill a gap in a season, and carries long honey scented purple flower spikes right through the warm months. It asks very little: full sun, drainage, and one hard prune a year.

Why you'll love it

• Butterflies actually turn up. The flower spikes are a nectar magnet, and bees work them just as hard.
• Fast cover. A tube planted in spring can be a 1.5m shrub by the following autumn in a warm garden.
• Real fragrance. A honey sweetness that carries a few metres on a still, warm day.
• Genuinely undemanding. Frost hardy, drought tolerant once established, heat tolerant and content in poor soil.
• Long flowering. Deadheading spent spikes brings on a fresh flush, so the display keeps repeating rather than finishing in a fortnight.

Where it works best

Feature and border planting. One plant at the back of a sunny border does the job, arching over lower perennials without shading them out.

Mass planting and informal screening. Plant 1.2m apart for a massed shrub border or a loose seasonal screen. It is a soft, informal barrier rather than a clipped hedge, and it thins out in winter.

Dry and difficult ground. Poor soil, heat and a well drained slope all suit it, which makes it useful on the strip nothing else holds.

Growing Buddleia 'Joan' in Australia

Position and climate. Full sun, all day. This is a warm temperate, cool temperate and Mediterranean plant, so it does well from Perth and Adelaide through to the cool south. It is frost hardy and welcomes a genuine winter chill. In the humid subtropics and tropics it grows soft and flowers poorly, so it is not the pick for the far north.

Soil. Drainage is the one real requirement. It handles poor, stony and alkaline ground happily, but wet feet in winter will kill it. Mound the planting hole on heavy clay.

Water and feed. Weekly deep watering through the first summer, then only in long dry spells. A light dressing of complete fertiliser in early spring is plenty; overfeeding gives leaf at the expense of flowers.

Pruning. This is the one job that matters. Cut the whole plant back hard in late winter, to roughly knee height, because it flowers on new wood. Skip it and you get a leggy, bare-bottomed shrub with small flower heads. Deadhead through summer to keep it flowering and to stop it seeding freely into nearby beds.

What to expect when it arrives

This one is grown in tubes. You are buying a young, single stemmed plant, usually 15cm to 25cm tall, not an instant shrub. That suits a fast grower like this: tubes establish quickly and catch up to larger stock within a season or two.

Because it is deciduous, a winter delivery may arrive as bare stems. That is normal, not a fault. Plants are delivered Australia wide, with delivery from $29.95 and a minimum order of $300 before delivery, and every plant carries our 30 day healthy plant guarantee. Expect first flowers in the first summer and full size by year three.

Plant care guides and related reading

• Browse plants that attract bees and butterflies
• Compare the deciduous shrub range
• A guide to planting for fragrance
• Orange Ball Tree, the taller orange flowered buddleia

Common questions

How far apart should I plant it?

Space plants 1.2m apart for a massed border or an informal screen. Given each shrub reaches about 2m wide, that lets them knit together while still allowing air through.

Does it lose its leaves in winter?

Yes, it is deciduous, and in cool gardens it drops everything. Treat it as a summer performer and pair it with something evergreen if the spot needs year round cover.

Will it take over the garden?

It sets seed readily and seedlings do appear nearby, so deadhead spent spikes before they brown off. That one habit keeps it well behaved and lengthens the flowering.