What to do in your allotment in March
Written by Lee Senior
The spring bulbs are out, the birds are singing and there’s a newfound feel-good factor in the world of allotments! March is one of my favourite times of the year as it’s full of optimism and promise.
As soon as I see signs that the soil is starting to warm up, I’ll be planting my early seed potatoes that were chitted last month. A good way to monitor soil temperature is by simply observing. As soon as the first weeds appear, it’s a fairly reliable indication! I’ll also be warming the soil in my raised beds with a sheet of black plastic ready for next month. The colour absorbs the rays of the sun, getting the soil ready for my new seedlings.
The next three months are the busiest of the year for seed sowing, both indoors and out. In March, our main focus is sowing under glass. This year, in my unheated greenhouse I’m sowing broad beans, Brussels sprouts, summer cabbage, cauliflower, courgettes, cucumber, lettuce, leeks, pak choi, peppers, sweet corn and tomato seeds. In the second half of the month, I’ll sow beans, pumpkin and squash. It’s been lovely to be able to work on the land again recently and there’s certainly plenty to do. Happy growing!
- Sow sunflower seeds into modular seed trays and pop them on a sunny windowsill to germinate ready for potting-on next month.
- You can plant your first early potatoes into well dug ground, along with second early varieties too. Try adding specific potato fertiliser to give the shooting and rooting tubers a boost.
- Direct sow parsnip seeds this month, but only after the last frost. They germinate best in constant temperatures, above freezing.
- The same is true for sowing beetroot, radishes, spring onions and carrot seeds outdoors this month.
- Direct sow hardy broad bean ‘The Sutton’.
- Plant onion and shallot sets directly into their allotment beds. Cover the rows with a long cloche to protect them from any unexpected late frosts, and from birds.
- You can also sow your spring-planting garlic sets in March, for an early autumn harvest.
- March is a good time to start sowing your vegetable seeds. Start them off under cover – either on a sunny windowsill, in the polytunnel or in a greenhouse. Tender crops like aubergines, cucumbers, sweet peppers, tomatoes, and lettuce seeds benefit from being sown in a heated greenhouse.
- In unheated greenhouses, sow hardier seeds like Brussels sprouts, summer cabbage, cauliflower, courgettes, leeks, pak choi, and sweet corn. In the second half of the month, sow crops like French beans, runner beans, pumpkin and squash.
- Sow broccoli seeds in modular trays under cover.
- Watch out for frost around apricot, nectarine and peach trees. These fruit trees blossom particularly early in the year and, if the blossom is damaged or drops, the fruit yield will be reduced. Protect the blossom with horticultural fleece if frost is scheduled.
- Feed your fruit bushes and fruit trees by mulching with well-rotted manure or compost. Make sure that the tree trunks are not in contact with the manure.
- Plant bare root fruit trees up until the end of this month. Add a handful of bonemeal to the planting hole and back fill with humus-rich soil.
- Harvest the last of the winter vegetables in March.
- Purple-sprouting broccoli should be prolifically cropping this month, so take advantage of all the fresh and tender stems that you can cut!
- Try to stay off waterlogged soil but, if you have to access the allotment, use planks to spread your weight.
- If you’re transplanting seedlings this month be careful to handle them by the leaves and avoid contact with the stem. Damage to the stem is irreparable whereas a damaged leaf is not so calamitous.
- Watch out for the first flush of weed seedlings this month. This is a good indication that the soil temperature is rising.
- Prepare your raised beds for direct sowing seeds at the end of March. Cover the soil surface with black plastic to warm the soil underneath.
- Invest in a cloche to advance outdoor sowing and improve the germination rates of outdoor sown seeds.
- Remember to carefully dispose of any spent winter crop plants. If they show any signs of disease like club root, don’t add them to the compost heap or you’ll spread disease around the allotment.
- Prepare all your beds for planting by digging in some good quality compost. If you use well-rotted manure, make sure it’s properly rotted down so it doesn’t damage the delicate roots of your seedlings.
- If it’s still very cold in your area, you could always insulate your greenhouse with horticultural bubble wrap. Or, invest in some frost protection fleece to cover seedlings.
- Protect your containers from impending slug and snail attack with copper tape.
- Put a feeder out for the birds to attract them to your allotment. Birds eat pests and should be a welcome sight around the plot.
- Use shading fabric in the greenhouse if the weather’s unseasonably sunny and warm. This protects seedlings from sun scorch.
- Plan to start watering next month by cleaning or installing water buts and checking watering cans.
- Check you have plenty of potting compost and containers for potting on all your thriving plants and seedlings in April.
Suttons Seeds recommend these areas which may also be of interest.
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