Plant this shrub to attract butterflies

The fat flower spikes of tiny blooms are nectar-filled, attracting bees and other beneficial insects, even small birds.

A beautiful monarch butterfly, feeding on the flowers of a butterfly bush.

One of the best shrubs to attract butterflies is called butterfly bush or summer lilac, bred from Buddleja davidii. The fat flower spikes of tiny blooms are nectar-filled, attracting bees and other beneficial insects, even small birds.

Some of the best taller varieties, around 2m-3m tall, include ‘Pink Delight’, ‘Black Knight’ (deep purple), ‘White Profusion’, ‘Royal Red’ (magenta) and ‘Joan’ (lilac). Buddlejas are fast growing, multi-stemmed shrubs with arching branches that bloom all of the warm months. A light prune after each main flush of blooms keeps the flowers coming. They love a sunny spot but will take part shade, and tolerate dry and salty conditions but need frost protection. They suffer few pests and diseases. The flowers have a sweet perfume and last for several days in a vase.

In winter, prune them back heavily. The original species from China with mauve flowers is considered weedy in many countries. In my Sydney garden, I’ve never seen the named varieties self-seed, but buddlejas are on the watch-list in parts of Australia.

Create a buzz

Breeders have developed hybrids that are sterile, limiting their potential weediness. In the “Lo and Behold” series, ‘Purple Haze’ and ‘Ice Chip’ are sterile, low, spreading varieties.

Buzz Hot Raspberry.

Buzz ‘Sky Blue’.

‘Spring Promise’ (white) and ‘Wattle Bird’ (yellow) are Australian-raised, non-invasive, tall varieties. The Buzz series of compact, free-flowering and sterile buddlejas is ideal for pots.

Buzz ‘Soft Pink’.

Buzz ‘Purple’.

Q&A

Can I prune frangipani trees that grew tall and thin while in pots down the side of the house?

Caroline Bell, Perth

You can prune frangipanis as hard as you like. Pruning at a branch fork limits new branches; to create a bushier tree, prune branches to half or one third their length. Winter to spring is the best time. It can take two years for new branches to flower.

If I dead-head agapanthus while the seed pods are still green, can I leave them on the ground or could the seeds germinate?

Dani Chatfield, Mt Macedon, Victoria

Agapanthus seed pods dry and brown when the seeds are ripe, but it’s possible for green pods to contain some viable seeds, even shortly after the flowers fade. Check inside pods – viable seeds are filled and black, while immature seeds that wouldn’t germinate are flat and pale.

My established lawn of different grasses is full of weeds. If I use “weed and feed” a few times, will it still look a patchy mix? Aside from returfing the lot, is that the best I can hope for?

Georganne Ylias, by email

“Weed and feed” products sound easy but do neither very well. You’ll get a better result by separately using a quality lawn fertiliser and then a selective turf weedicide, where needed. Weedicides work best when weeds are growing strongly, so fertilising (along with watering) boosts both lawn and weeds. After 10-14 days the weeds ideally will be taller than the grass and their lush, open leaves will absorb most of the weedicide. Check the soil pH is around 6-7, as acidic soil can favour weeds (apply garden lime if it’s acidic). With regular mowing, fertiliser and water you should achieve a reasonably even, green lawn, despite the different grass types.