What to do in your allotment in March

Broad Bean Seeds ‘The Sutton’ from Suttons

Written by Lee Senior

The recent storms and heavy rains of late February temporarily subdued any thoughts of an early start. High winds caused tremendous damage to fences and polytunnels and, in some cases, sheds, on the more exposed allotment sites.

Good weather in Spring is critical – it sets the tone for the year ahead and helps to get everything off to a good start. Spurred on by some warmer sunshine, seed sowing has become our main focus. Most of our sowings are under cover, indoors. However, towards the end of the month, direct sowings into raised beds or well-drained areas may be possible.

Later this month, when the soil is ready, early varieties of chitted potatoes can be planted outside, in well-drained soils. If your soil is heavy and slow to warm up, tubers can also be grown in pots. However you grow them, potatoes are very susceptible to frost. It’s essential to keep a roll of fleece ready when those young shoots emerge. Cloches or portable polythene tunnels are great also for trapping heat in the soil as well as protecting young seedlings. Having a good range of protection for your young plants greatly expands what you can grow on your plot. Happy growing!

Allotment flowers in March

  • This month colourful crocus flowers linger on and are supplemented by daffodils and muscari.
  • There are a number of miniature daffodils, perfect for containers. I like the dwarf variety ‘Tete a Tete’. For something different try the double-flowered, multi-petalled, ‘Rip Van Winkle’.
  • The blue muscari ‘Armeniacum’ looks great under trees or in semi-shaded areas and flowers towards the end of March into April.
  • Sow sunflower seeds into modular seed trays and pop them on a sunny windowsill to germinate ready for potting-on next month.

Allotment vegetables in March

  • A good way to tell if the soil temperature is increasing is by observing the weeds. As soon as the first flush of weed seedlings emerge, this is a key indicator.
  • Sow Brussels sprouts F1 ‘Brigitte’ or F1 ‘Crispus’ in a cold greenhouse or on the windowsill.
  • In a heated propagator, sow Cucumber F1 ‘Delistar’.
  • I’m a huge fan of purple carrots and my kids love them too. At the end of the month and into April, direct sow F1 ‘Purple Haze’ into well-drained, freshly prepared ground that has been pre-warmed with a membrane. 
  • At the end of the month, early Beetroot ‘Boltardy’ can be direct-sown.
  • I prefer to sow early pea seeds in gentle heat indoors and then transplant later in spring. This maximises germination potential. The second early variety ‘Hurst Greenshaft’ is ideal.
  • Sweetcorn needs a relatively long season and seed should be sown in March in gentle heat. Take care not to overwet the compost as the seeds can be prone to rot. Protect from frost. 
  • Lettuce ‘Unrivalled’ is perfect for spring sowing in trays for transplanting. At this time of year I sow under glass but as the soil warms up the seeds can be sown directly.
  • Courgettes are one of my favourite crops. They have many uses and are easy to grow. Sow the seed in March and April in gentle heat and protect from frost.
  • Early varieties of chitted potatoes can be planted, provided the soil is not too wet. Protect them from frost.

Allotment fruit in March

  • Blueberries are a super fruit to grow. Unless your soil is naturally acidic, plant the bushes in large pots of ericaceous compost.
  • The end of March signals the end of the bare-root fruit planting season. Pot-grown fruit trees can be planted all year round.
  • Prune established autumn-fruiting raspberries almost to ground level before new growth commences.
  • Clear out any dead strawberry plant foliage to encourage a good air flow to the base of the crowns.
  • Keep an eye on the blossom belonging to apricots, peaches and nectarines. It can be damaged by frost so it’s worth covering the tree with fleece if you’re worried. Alternatively, if you’re lucky enough to have the space, why not grow a dwarf peach tree in a pot in a polytunnel, like my neighbour does?

Crops to harvest in March

  • My Brussels sprouts have just about finished now and what a wonderful crop it has been! The flavour of modern varieties is far superior and less bitter than older varieties.
  • Purple broccoli is now cropping heavily and the young heads are so full of flavour. I did have a minor setback when the recent gales blew off my netting, leaving some plants uncovered and at the mercy of the local pigeon population.
  • Kale, winter cabbage and Jerusalem artichokes are in season.
  • I’ve now run out of leeks after a bumper crop, but I plan to sow even more this year to remedy this.
  • Parsnips are still going strong but it’s noticeable the tops are starting to grow just a little. When this happens they should be okay for another two-to-three weeks before they start to become unusable.

General March allotment jobs

  • 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.
  • 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 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.

Planning ahead

  • 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.
Lead image: Broad Bean Seeds ‘The Sutton’ from Suttons
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About Lee Senior
Lee Senior is an experienced horticultural writer, RHS Yorkshire in Bloom judge and horticultural consultant. He has also had an allotment for over 25 years. After initially spurning horticulture as a career option, to pursue his boyhood dream of becoming a train driver, Lee soon realised he couldn’t resist getting his hands dirty to make a living. Horticultural College training led, to getting an allotment at the tender age of 18 (in the days when you could actually get a plot quickly). My gardening hero, is Geoff Hamilton” says Lee. “It was Geoff who convinced me that you didn’t have to spray everything that moved in the garden. Watching him on Gardeners’ World in the late 1980’s and early 1990’s was a revelation. I was lucky enough to meet Geoff and I’ve also more recently had the pleasure of meeting Joe Swift. Now over two decades of practical experience has taught me to work with mother nature, not to fight against her and don’t try to tame her, as so many gardeners seem to be on a mission to do. Small-scale food growing is my passion and I can’t wait for my two daughters, one who is 8 years old and the other who is 5 to hopefully pick up the baton in the future. Nothing beats the flavour and satisfaction of growing your own food. You simply cannot buy the same quality and freshness. Everyone can have a go at growing something says Lee, no matter where they live. Lee has also written his two books; ‘Pennine Way, The Highs and Lows’ which is a humorous, personal account of walking this momentous iconic walk. His second book ‘Walking in the Aire’, features 14 short walks in Yorkshire.