Bee Plant of the Month - July
Lavender's Blue, Dilly Dilly ....
No, I’m not taking up folk singing (thank goodness, I hear my musical friends cry!), rather it seemed a good title for my post on lavender (Lavandula).
I know I briefly mention lavender in my View from The Wine Shed post (8th April 2020) but I thought it deserves a post all of its own.
I can’t remember a time when I haven’t grown lavender. Even when I lived in flat and the only ‘garden’ I had was a window box, I forsook all other plants and was faithful to my lavender. And it was my all-time favourite that I grew: L. angustifolia ‘Hidcote’. Cultivated by Lawrence Johnston, owner of Hidcote Manor in the Cotswolds until the late 1940s, it has become, arguably, the best-known, and best loved, of all the English lavenders.
So lavender is native to England, then? Actually no, although it’s been growing here for centuries. All species of lavender are native to areas such as the Middle East, southern and central Europe, north Africa and south-west Asia. It’s thought that it was introduced to Britain by the Romans, although the first written reference to it doesn’t appear until 1265.
We do know that Gerard in his 16th century Herbal advocates lavender as a help for ‘them that have the Catalepsy, a light migram, and to them that have the falling sicknesse […] panting and passion of the heart, giddinesse, turning, or swimming of the braine’. Queen Elizabeth I carried posies of lavender and other sweet-smelling herbs to reduce the effect of unpleasant smells (stench more like), and the flowers were used extensively for culinary purposes throughout the centuries – apparently Queen Victoria liked lavender jelly rather than mint with her lamb. I love lavender scones (made with a plain scone mixture with a pinch of lavender flowers) eaten with home-made lemon curd and clotted cream – yum.
Lavender really came into its own in England in the 19th century when the hardiest of the lavenders, Lavandula angustifolia, began to be grown on a commercial scale for its essential oil, used in the perfume industry. In fact, the product was so consistently good that perfumiers (even French ones) would specify that they wanted English lavender – and that’s how Lavandula angustifolia came to be known as English lavender.
Commercial production in Britain waxed and waned, and is now waxing again and you can visit numerous lavender farms that open their gates to the general public.
But back to my window box. All lavenders need the sun with really free-draining, verging on poor, soil which is what I could give them in my container. In the garden it can be a bit trickier to meet these optimum requirements, but fall short and your lavender with sulk and give up the ghost. If you want to keep them overwinter you need to grow the hardiest types, namely L. angustifolia or L. x intermedia (the latter is a hybrid of L. angustifolia subsp angustifolia and L. latifolia) Both are hardy in the UK to -15˚C.
But which variety to choose? In one nursery catalogue there were no less than 18 varieties of L. x intermedia, and 30 of L. angustifolia. So, let’s think about criteria: what colour – there are white and pink as well as lavender-coloured; how tall – some reach 90cm, others just 40cm; decisions, decisions. The one decision you won’t have to make, however, is which ones are best for bees, because all varieties of L. angustifolia and L. x intermedia are, although some appear more attractive than others.
The University of Sussex carried out research in 2014 about which plants are best for bees. (The results were published 6 years ago in Functional Ecology Volume 28, pages 364–374, but I don’t think the bees will have changed their minds much over that period of time.) They focussed on Lavender in particular and trialled 6 each of L. angustifolia and L. x intermedia, all of which were readily available at nurseries. Of the six varieties of L. angustifolia, ‘Hidcote’ and ‘Folgate’ were the most popular with bees, and ‘Edelweiss’ and ‘Gros Bleu’ were the favoured varieites of L. x intermedia. (See below)
Interestingly, lavender attracts more bumble bees than honeybees. There is a particular reason for this which is related to the length of the bees’ proboscis (the hollow tongue through which they gather the nectar) and the depth of the lavenders’ corolla tube (the fused petals of the individual flower which are shaped like a tube). The length of a honeybee’s proboscis is approximately 2mm shorter (at 6.6mm) than that of bumblebees (7.8-8.9mm) which means that bumblebees can more readily access the bottom of the corolla tube (approximately 7mm) where the nectar is to be found.
In addition, it was found that bumblebees extracted the nectar more quickly than honeybees, therefore being able to visit more flowers in the same given time.
So, it seems that the poor little honeybee is being outcompeted by their longer-tongued cousins. But don’t despair, honeybees will still visit, even though they will be outnumbered – they can’t resist the nectar.
Let’s have a quick look at the bees’ favourite varieties now.
First L. angustifolia ‘Hidcote’. This is a dark purple variety with grey foliage which grows to about 50cm. Be sure to get your plants from a reputable source – there are an awful lot of imposters out there!
Second is L. angustifolia ‘Folgate’. This variety has ‘bluer’ flowers than ‘Hidcote’, with slightly greener foliage, It grows to about 60cm.
Third is L. x intermedia ‘Edelweiss’. As its name suggests this is a white variety; it grows to about 75cm forming a domed bush, so allow it plenty of space.
Last is L. x intermedia ‘Gros Bleu’. This is an introduction from France, which, colour-wise, is similar to ‘Hidcote’. It’s taller than ‘Hidcote’, though, growing to about 75cm.
And finally – time for tea in my favourite mug!