March is often the first month that really feels like Spring. It brings the equinox (20th March, when day and night length are the same), we switch to Summer Time (27th March) and we gain almost two hours of daylight over the month, as sunrise and sunset times extend. So we tend to enter our gardens with renewed enthusiasm, hopeful that the worst of the weather is behind us and eager to see what’s started to grow. Here’s our round-up of key jobs this month.
Well done if you have managed to hold off clearing up your garden until now! You probably can’t see them, but there will be many beneficial insects sheltering amongst the seed heads and foliage that you’ve been good enough to leave them. It’s generally recommended that you don’t do a big tidy until daytime temperatures are regularly 10’C (50’F) or more, so that all those insects aren’t made homeless in the cold weather.
Clear out and compost old foliage and stems around the garden, ready for the new growth to appear. Don’t forget to remove newly germinated weeds, too, before they get too big. And, if you can, mulch your newly cleared beds and borders with a generous layer of compost to help retain moisture and suppress further weed growth.
As the days lengthen, now is the time to think about letting more light into your greenhouse. If you’ve added extra insulation (like bubble wrap) for the winter, you can remove it now. It’s also a good time to clean all the windows, inside and out, to maximise the light and get rid of any hidden bugs. Please don’t use chemical cleaners, though; a solution of hot, soapy water is generally good enough but household ingredients like white vinegar, lemon juice and tea tree oil can give an antibacterial boost. (We found this great selection of homemade cleaners on the Good Housekeeping website that we think would be worth a try: Good Housekeeping
As well as light, think about letting more air into your greenhouse, potting shed or cold frame too. Opening doors, windows and vents on sunny days helps prevent a build up of humidity that may encourage moulds and mildews.
As your daffodils and other spring bulbs go over, pinch off the spent flower heads but leave the foliage to die back naturally. It’s the sunlight that the leaves can take in now that will send energy back into the bulb ready for a good showing next year. Cutting off the stems and leaves might look tidier, but it will almost certainly mean you have poorer displays next spring.
Deadheading any winter or spring bedding plants will help to keep them flowering a little longer, too. And it’s not too late to prune roses if you haven’t had the chance yet. (Refer to this handy RHS pruning guide for advice on your particular type of rose: Guide
Although some seeds will germinate earlier, especially indoors, March is really the month when seed sowing begins in earnest. Indoors, you can start most annual summer plants (like black-eyed Susan or cosmos), salad crops destined for the greenhouse (tomatoes, chillies, aubergines) and even get a head start on crops that will eventually go in your vegetable plot (lettuce, parsley and runner beans, for example).
If you’re keen to start sowing outside, you can help your soil to warm up by placing cloches or glass over it. Crops like parsnips are slow to germinate and need a long growing season so get them in the ground now. Other hardy veg, like spinach, can be sown outside too, although you might want to cover them with fleece or a cloche until they get established. If you’re sowing carrots in the ground, you’ll want to protect them too, but more from carrot root fly than the weather! (The Gardeners’ World tips on avoiding carrot root fly are invaluable, here: Gardeners World
As perennial plants – like lupins and dahlias – start bursting into life again, now can be a good time to take cuttings from them. Select a healthy young shoot (what we’d call ‘softwood’ because it’s still flexible) that doesn’t look like it will carry a flower head and is between 5-10cms long (2-4 inches). With a clean and very sharp knife or secateurs, cut the shoot from the main plant, preferably close under a node or leaf joint. As soon as you can, remove most of the leaves and push the shoot straight into a pot of moist but free-draining compost. If you can’t plant it immediately, seal the cutting in a plastic bag to prevent it loosing moisture until you can plant it.
Set the pot somewhere sheltered and keep it moist but not saturated (as your cutting will just rot). When you can see roots at the bottom of the pot and signs of new growth at the top, you know you’ve been successful and you can pot on your ‘baby’ plant. Of course, some plants will naturally take longer than others to ‘take’ so don’t give up too soon!
Some gardeners choose to dip the end of their cutting into rooting hormone (auxin) before sticking. Rooting powders also contain fungicides which inhibit basal rot. This can help cuttings take but is never a guarantee. Picking healthy shoots during their spring growth ‘spurt’ and planting them quickly is the key.