With lawns to mow and lettuces to sow, May is a busy month in the garden, says Sue Bradley
Sue Bradley reveals what to do in the garden in May, plus an Open Garden in Lot-et-Garonne
May is here and the warmer weather means it’s a great time to let rip with packets of lettuce seeds. Some gardeners will have already got a head start by sowing under cover in order to bring on part-grown plants to transfer outside later on.
But by now it’s possible to put seeds directly in moist soil ready for bumper crops of salad leaves in the months to come. The optimum temperature for germination for most lettuce seed is around 15°C, although some cultivars are known to sprout in cooler conditions.
Sow every two weeks for a succession of lettuces that can either be harvested all in one go or plucked ‘cut-and-come-again’ style for just a handful of leaves as needed.
Some gardeners like to grow lettuces in rows while others use them as ornamental additions to potagers.
They can be used as ‘fill-in’ crops between longer-maturing roots such as parsnips or carrots and are so flexible that they can even be brought on in containers or window boxes.
Once a growing space has been identified, the question then is which lettuces to sow.
We’re all familiar with the likes of ‘Cos’, ‘Little Gem’ and ‘Lollo Rosso’, but these are just the tip of the iceberg – no pun intended – when it comes to the huge choice that’s available.
Loose-leaf lettuces are fast growing, colourful and have open heads that make ‘cut-and-come-again’ cropping especially easy. They include red and green ‘oak leaf’ types, such as the French heirloom varieties ‘Feuille de Chêne Rouge’ and ‘Feuille de Chêne.’
Butterheads get their name from their soft and sweet ‘melt-in-the-mouth’ leaves and are well suited to being grown in spring and early autumn. Among their number are the French cultivars ‘Merveille des Quatre Saisons’, which has green leaves tinged with red or bronze, and ‘Appia Laitue’, with its green foliage. ‘Tom Thumb’ is small but perfectly formed, while ‘All Year Round’ is great for successional sowings.
‘Cos’, known as ‘Romaine’ in France, have upright heads, crunchy leaves, firm midribs and a slightly stronger flavour. This staple of the Caesar salad includes ‘Little Gem’, one of the earliest lettuces to mature, and ‘Nyams’.
Crispheads, or icebergs, have crunchy leaves and firm white hearts. They include the old English cultivar ‘Webbs Wonderful’, along with the bolt-resistant French ‘Reines des Glaces’, also known as ‘Ice Queen’, and ‘Salade de Russie’, which was introduced from Russia towards the end of the 19th century.
If the prospect of choosing just one or two cultivars is too restricting, opt for a mixed packet, the lettuce from which will trump supermarket salad bags every time.
When it comes to pests, slugs are one of the worst menaces when growing lettuce, although these can be controlled using pellets, or, for organic gardeners, beer traps, copper tape, grit or nematodes.
Alternatively, grow lettuce in pots until a reasonable size before planting out to give them a fighting chance against the molluscs.