How to grow Lavender
How to grow Lavender
It's hard to imagine a plant which is more evocative of summer than lavender, with its intensity of colour and scent. Looking at the images you can almost hear the bees. Lavender is ideal for a mixed border but it also makes a fantastic edging plant and a lavender path is a lovely garden feature. Not only does it look beautiful but as you walk along the path the lavender releases its familiar scent. Like so many plants Lavender is easy to grow in the right condition and hopeless in the wrong conditions. To do well, Lavender really needs sun, well drained soil and dislikes wet, especially winter wet which it will not tolerate and this can cause the plant will die in part or completely see image below. All this means when growing Lavender you do need to pick the right spot.
Thought of as a quintessentially English plant, Lavender is part of the genus Lavandula with about 39 species many found in the Mediterranean and warm climates. Given its origins Lavender prefers, in fact needs, good drainage and a sunny spot. It the ground tends to be wet, even the hardiest lavender (see below for which are the hardiest) will struggle to survive a winter with their roots in wet. Lavender is a great border plant which looks good at the front of a border spilling over. It mixes well with hardy geraniums, Alchemilla, roses, Artemisia, Campanula, and Achillea.
There are two main types of lavender generally available: Lavandula Angustifolia (***) known as English Lavender images left and right L. Hidcote, Munstead which are the most hardy of all lavenders, and French lavender Stoechas (**) illustrated centre.
Best Growing conditions for Lavender
English lavender, (which is not native to England) is more hardy than the French variety and provided it is not too wet will survive the winter, but only in the right conditions. Lavender really hate having their roots in cold wet soil, and it's the wet which is the real problem. To give Lavender the best chance of success choose a spot which is sunny and has well drained soil. To plant Lavender dig a hole about 3/4 inches bigger than the plant you have purchased and tap out the plant from the pot, tease out the roots, which means put you hand in the roots and free a few gently. Water and plant so that the level of the soil from the potted plant is the same as the earth, and firm it in so it's secure and no air pockets.
If your soil is not suited to the lavender requirements, i.e. not well drained, you can help by improving drainage which is best achieved by adding horticultural grit, (sold at all garden centres.) If your ground is particularly heavy, with clay, tending to water log in winter it will be necessary to dig a trench to create a greater area of free draining soil either where you are planting or along side the path to improve the drainage.
If you garden in one of the colder areas of the country, especially if the area/plot is on the wet side the lavender will be unhappy and are better in pots and under glass/sheltered in the winter. If it is a bad winter and the temperature goes well below freezing on a consistent level lavender may well not survive. Lavender plants are in any event a short lived perennial; up to 10 years in perfect conditions but often become leggy, woody and with bald spots after a few years and are best replaced.
Illustrated below is how a lavender can look after a wet cold winter, much of its foliage is damaged . Whilst the lavender will recover, at least in part, it may not look brilliant and if your conditions are cold and wet it maybe necessary to consider what else to grow instead of lavender? If you have no success with lavender because of the growing conditions, but want that type of effect, the next best substitute is Nepeta (Cat Mint) Although often dismissed as a cottage type plant Nepeta is a long flowering perennial which although preferring dry conditions, it is not nearly as fussy as Lavender. It is true cats like the smell when the leaves are rubbed together. Some varieties get quite large, such as six hills giant nearly a metre. Nepeta is a good candidate for the Chelsea Chop to restrain it and make a more compact plant if needed. Nepeta can look very effective when massed together to create a Lavender type effect where the conditions are such that Lavender just will not thrive. If you are thinking about Growing Lavender but realise the conditions are not favourable take a look at Nepeta which is seen grown in many show and RHS gardens. The image below shows how planting scheme using Nepeta instead of Lavender to good effect. Another possibility is to grow Perovskia atriplicifolia, Russian Sage, illustrated below right, which grows a bit taller than lavender, is much loved by bees and far more tolerant of cooler wetter conditions.
When Lavender is provided with the correct growing conditions it needs very little care. It does not need feeding or frost protections unless growing a more tender variety such as French lavender, latin name Lavendula stoechas. Many gardening guides advise in late summer after flowering, to trim lavender cutting off the spent flowers and into the green growth of the plant to create a good shape for next year and this will also prevent the plant from getting leggy. This is good advise, but I am very reluctant to trim lavender after flowering as I like the sight of the fading flower heads. If you don't trim back in the summer, prune in April the same way, (not too early or the frosts can damaged the pruned stems) just trimming off the spent flower heads and into a nice shape. Always avoid cutting into the old wood which is the established part of the plant unless it is looking very bare when you may want to prune away old wood to improve shape and appearance.
Lavender tend to be short lived and over a few years will become leggy, more woody and tending to be bare in the centre of the plant and flower less well. The best thing to do at this stage is to replace the entire plant.