May Gardening Tips

The weather should be getting warmer by now and days are certainly longer so there’s more time to spend in the garden in May. You may find that there are still lots of the jobs from April that can be brought forward into May, depending on where you live, especially here in the Highlands where a lot of our spring bulbs are still flowering! Here’s our top May gardening tips.

Top Tips for May

  1. Continue to keep weeds under control by regular hoeing and mulching troublesome areas within the garden. This is a great job for the whole family to get involved with! (See our Tips for Weeds page)
  2. Feed hungry trees, shrubs and roses with a balanced slow-release fertilizer, scattering it on the soil and forking in lightly. This will aid their flower growth for strong and healthy blooms over the next few months.
  3. Continue to monitor trees, shrubs and perennials planted during the autumn and this spring, watering thoroughly when required to continue plant establishment.
  4. Prune spring flowering shrubs and perennials when flowers fade. Examples being forsythia, chaenomeles, pyracantha, ribes and kerria. Prune forsythia once it finishes flowering, cutting back to vigorous young shoots. Trim lavender and winter-flowering heathers to stop them getting leggy, taking care not to cut into old wood when pruning lavender.  Now is also the time to take cuttings of these to build up stocks.
  5. Mow lawns with a higher blade setting and continue to repair bare patches. Don’t forget to feed established lawns!
  6. Tie in climbing and rambling roses, bending stems to lie as horizontally as possible to encourage them to flower all along their length. Tie in new honeysuckle and clematis shoots as well.
  7. Put supports for tall perennials in now, while the plants are small and it’s still easy to work around them. This also lets you train the plants through the supports as they grow.
  8. Lift and divide perennials and ornamental grasses, rejuvenating them and giving you more plants. April’s also an excellent time to plant new perennials and shrubs.
  9. Trim ornamental hedges, however look out for nesting birds – don’t touch those ones!
  10. Harden off cutting of dahlias and chrysanthemums for planting out at the end of the month, along with tender bedding plants and perennials.
  11. Feed fruit trees and soft fruit with a high potash fertilizer. Prune plums and cherries now the sap has risen. Put up pheromone traps in apple trees to deter codling moth, and another type specific for plum maggot by the middle of the month.
  12. As the soil warms up, sow hardy annuals like herbs and wild flowers like cornflowers and poppies outdoors for fabulous summer colour. In the greenhouse, sow tomatoes, courgettes and pumpkins in small pots for planting out in June.
  13. Sow seed outdoors for beetroot, carrots, Swiss chard, summer cauliflower, kohl rabi, lettuce, leeks, radish, turnip, spring and pickling onions, peas and perpetual spinach in well-prepared soil.
  14. Protect potatoes from frost, and developing tubers from sunlight – keep topping up soil in containers as the potato plants grow.
  15. Continue to tackle pests and disease early. Protect young seedlings against slugs and snails with grit barriers, copper tape or pellets. Wipe aphids off rose leaves to stop infestations developing, and spray roses with fungicide against blackspot

Get Growing This May

The HTA’s ‘Gardening is good for you’ campaign is all about encouraging everyone Get Growing in May – sow and plant flowers, veg, salads, fruits and herbs to enjoy over the months ahead. By growing your own you’ll pick the freshest, healthiest, nutrient-rich produce possible …. from plot to plate in minutes!

To visit the HTA’s May, ‘Get set… grow’ page click HERE.