5: What to do in the garden in May

As one of the best months for gardening, you will notice your garden truly coming to life in May, 

Helped along by the good weather at this time of year many plants will be getting themselves ready for a spectacular summer display. The weather is usually quite pleasant in May, you can expect temperatures to be warming up but do be aware of any late frosts before tendering plants outside for the summer months. Remove any frost protection towards the end of the month so you can be confident to miss the last, late frosts.

If you are planning on laying new turf or lawns, it’s best to do this before it gets too dry, so keep an eye on the forecast as It is generally much drier and warmer in May than previous months. If you have a greenhouse, make sure to ventilate regularly and place any young plants in the shade away from direct sunlight. 

Make sure to keep all newly planted trees, shrubs and plants well-watered during dry spells as especially once first planted out and add a layer of mulch to help with water retention within the soil. This is also the time to ensure all weeds are kept on top of and nipped in the bud early, do this by raking or hoeing the ground to catch them before they develop and spread. 

Enjoy the warmer weather this month and watching your hard work starting to pay off in the garden! 

Important: don’t forget to keep an eye on plants regularly for signs of pests!

Ornamental Garden:

  • This month is a fast period of growth. Late frosts may catch early blooms, remove any damaged growth.
  • Spray roses with Rose Clear or similar.
  • Keep on top of weeding. 
  • Continue to remove spent flowers of spring bulbs but not the foliage until it has withered and yellowed.
  • Chelsea-chop time. If the Nepeta and Sedums are looking leggy then cutback by a third to encourage compact growth that will not collapse later in the season. This can be applied to the Lavender, Echinus, Echinacea, Aster, Helenium and Salvia too if felt necessary.
  • Trim Rosemary, Thyme and Sage if not done in April.
  • Cutback withered Daffodil or Tulip stems once they have turned yellow.
  • Trim grass edges of borders regularly to keep neat and tidy.
  • Prune spring flowering Clematis after it has flowered.
  • Stake and support Herbaceous perennials if necessary.
  • If Daffodils gave a poor show lift and divide bulbs and replant.
  • Continue deadheading spring bulbs.
  • Start hardening off tender plants for planting out.
  • Plant out Dahlias towards the end of the month.
  • Protect new plants from hungry slugs and snails.    

Vegetable Garden:

  • Harvest Asparagus.
  • Direct sow French Beans and sweet corn if weather is warm enough.
  • Start earthing up Potatoes. 
  • Harvest early crops such as radish and lettuce.
  • Avoid planting Tomatoes too early as they suffer if exposed to temperatures below 12°C.
  • Sow Pumpkins, Cucumbers, Courgettes, Squashes under cover now and outdoors towards the end of the month.
  • Lift and divide Mint. 
  • Mulch fruit plants

Other jobs to do in the garden in May:

  • Feed & mow established lawns.
  • Apply treatment to weeds within lawns.
  • Keep on top of weeds by regularly hoeing ground.
  • Keep the garden tidy and free of debris.
  • Keep on top of watering. If the weather is warm make sure to do this daily to ensure the ground isn’t dry.