Diarmuid Gavin: In the loop
Once deemed cheesy, the lupin is now back on trend
The lupins in my garden started flowering early this year. Although - like a Euro-pop song - they can be perceived as a little cheesy, these plants are my garden guilty secret.
My interest in them was rekindled when they became the stand-out plant at the Chelsea Flower Show. What's displayed at the show matters and when a group of designers or growers use a certain species in an innovative, fresh way, you look again.
Before that, I suppose I had regarded them as a plant for the mixed border - one of those rather garish collections of fruit-salad colours favoured by old-timers; a plant that has been grown beside rows of vegetables for years. In the Great Marquee at Chelsea, they are displayed every year in a very striking manner: row after row of perfect upright blooms in the most vivid, almost psychedelic, colours. But occasionally they make their way over to some of the show gardens on Main Avenue.
A couple of years ago, the overall winner of the show - a Laurent-Perrier-sponsored garden - had lots of yellow Lupinus 'Chandelier' planted to great effect amongst a field of Orlaya grandiflora, those lovely white flowers a bit like lace-cap hydrangeas. That same year, the People's Choice Award went to Matt Keightley's Hope on the Horizon garden, which was studded with Lupinus 'Red Rum'. Thus lupins were rehabilitated as a designer garden species.
So, why the re-evaluation? They're great value, for starters: they grow easily from seed and are not demanding in terms of soil. They are nitrogen fixers, which means they can convert nitrogen from the atmosphere into nitrates in the soil. This allows them to thrive on poor soil and, indeed, improve the soil when they die.
Normally, they start into growth after the last frosts, produce their first flush of flowers in late May/early June and can continue flowering into early August if religiously deadheaded. They grow to a height of 1m-1.2m/3ft-4ft depending on soil and weather conditions. Lupins support themselves, even in windy conditions, and do not need staking. They're the perfect cottage-garden plants, adding height and structure to an informal border, with candles of flowers in a rainbow array of colours. Bees and butterflies love them, so they are good for the wildlife-friendly garden. If you cut down spent flower spikes after flowering, they will often give an encore, albeit of smaller flowers.
They're not entirely problem-free, however. They can suffer from a fungal disease which causes dieback and leaf browning. When this gets hold, it's hard to control and it spreads easily in wet weather. One preventive measure is to allow sufficient air circulation around your plants by not stuffing them in too closely. Aphids such as the greenfly are great fans of lupins and like to suck sap from them to the point where the lupin will wilt. You can either remove the aphids by hand or with a hose, or there are sprays available, both organic and chemical, that you can apply. They are also a favourite snack for slugs and snails.
Lupins are tap-rooted members of the pea family and therefore difficult to divide into many pieces. They are not long-lived; they may last for seven or eight years. They make up for this by setting a lot of seeds. But the seedlings can be very variable - although, with constant selection, a strain can become quite stable. There are plenty of cultivars to choose from but if you like trying out a variety, Thompson & Morgan have bred Lupinus 'Tutti Frutti'!
MY TOP TIPS FOR GROWING LUPINS:
* Plant when young so that they can put down a good root system, in an open position away from trees.
* Lupins love a sunny site, although they can be grown successfully in light shade.
* Lupins are not great fans of chalk. However, I have managed to grow plants in limestone soil.
* They prefer a moist, well-drained soil - add a bit of grit when planting if your soil is heavy - but can be grown in most garden conditions. They do not like being waterlogged, which can rot the crown.
* They don't take too kindly to being chopped back hard after flowering - they take months to recover.
* If you have a good plant, don't let it produce lots of seeds. Keep the vigour in the parent plant and deadhead as the flowers fade. Never divide in autumn.