Experts reveal the one plant you should grow to attract butterflies to your garden

The humble buddleja grows profusely on waste ground and railway embankments, but a delicate magenta-flowered variety of this common shrub, Buddleja davidii Little Ruby ('Botex 006') (Butterfly Candy Series), was shortlisted for the RHS Chelsea Flower Show Plant of the Year 2022. 

It lost out to winning plant, × Semponium 'Destiny', a dark purple succulent, but buddleja’s appearance on the 20-strong Chelsea shortlist reminds us of its importance in bringing butterflies and other pollinators to the garden. 

So if you're looking for the best ways to grow a butterfly garden, there are plenty of reasons why you should consider putting buddleja on your planting list.

'Buddleja is always top of the list of most commonly-used nectar sources in our Garden Butterfly Survey and lives up to its alternative name of the Butterfly Bush,' says Karen Goldie-Morrison, chairperson of the Butterfly Conservation charity. 

'The plants are also highly attractive to moths, bees and other insects,' she adds. illustrating why it's one of the best plants for pollinators. 

Avoid the invasive variety

However, choose your variety carefully. Some, such as Buddleja davidii, which grows wild, can sometimes be considered an invasive plant, particularly in the US. This variety produces lots of small, light seeds, which spread like wildfire. Seeds will settle pretty much anywhere, even in cracks in buildings, where they can damage the brickwork.

Buddleja davidii also forms rapid thickets in natural habitats such as chalk grassland. 'These places support a large number of invertebrate species, some of which are rare and endangered,' says a spokesperson for the bird charity RSPB. 

'Buddleja davidii can quickly cover open ground, which means those special species can no longer live there.'

Experts recommend this variety

If you’re looking for a buddleja for your garden or backyard in the US, the National Garden Bureau recommends Southern Living Butterfly Towers, an RHS Chelsea Plant of the Year finalist in 2019. 

'Available in magenta or white blooms, the profuse flowers beckon butterflies, bees, and hummingbirds, appearing in summer and blooming through fall,' says National Garden Bureau spokeswoman Gail Pabst. 

'The unique vertical habit makes a pretty hedge or screen.' 'Butterfly Towers' grows four to five feet tall and two to three feet wide. It enjoy full to part-sun and is suitable for USDA zones 5a-9b. 

'Butterfly Towers' is available from Southern Living in the US and Thompson & Morgan in the UK. 

It's worth remembering that pruning buddleja correctly is also advised to keep your butterfly-friendly bush under control.