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May in the garden

May in the garden - Blog Header

May has arrived and the risk of frost has passed so there's plenty of planting to do! 

Summer is on its way and it’s time to tidy up spring plants, plant out summer flowers and finally start to spend some time out relaxing and enjoying your garden.


Purple lobelia flowers

What to plant in your garden in May 

Risk of frost in the garden should have passed by May so plenty of herbs, vegetable and flower seeds can be sown directly outdoors now. Tender plants like cucumber can be sown indoors now too.

Seeds to sow this month

Salad and herb seeds to sow in May:
  • Rocket
  • Basil
  • Dill
Flower seeds to sow in May:
  • Cornflowers
  • Sunflowers
  • Zinnias
  • Scabious (pollinator friendly)
  • Nasturtiums
Vegetable seeds to sow in May:
  • Beetroot (great for beginners)
  • Sweetcorn
  • Carrots
  • Courgettes
  • Runner beans
Colourful cornflowers in the sun
This month you can plant out:
  • Strawberry and gooseberry plants 
  • Dahlia tubers and canna lilies 
  • Make up your own hanging baskets but keep in a porch or greenhouse for a few weeks first to give it chance to bloom 
  • Summer bedding can be planted out towards the end of May
Here are your main jobs in the garden this May:
  • Prune spring-flowering shrubs after flowering
  • Trim lavender plants, cutting off old flower heads and about 2.5 cm (1 inch) of the current year’s growth
  • Continue to weed beds and borders to prevent competition for water and nutrients
  • Harvest asparagus spears when they’re no more than 18 cm tall
  • Thin out direct-sown vegetables such as spinach, carrot and lettuce seedlings, then water the rows well
  • Pinch out the growing points of broad beans as soon as beans start to appear at the base of the plant to reduce the risk of blackfly attack
  • Weed around your onions and garlic to reduce competition for nutrients and water
  • Make supports for your runner beans, using 8ft (2.4 m) bamboo canes
  • Harvest rhubarb, picking only one-third of the total amount of stems
  • Apply lawn weed killer to your lawn this month
  • Top up bird baths and bird feeding stations to encourage birds into your garden