Advice for the gardener

Top Tips for May

  • Lawns will be growing strongly but don’t cut too low
  • On sunny days make sure that the greenhouse windows are open and plants are not drying out
  • Time to sow herbs and vegetables including parsnips, early carrots, runner beans, tomato, pepper, aubergine and cucumber
  • Harden off summer bedding plants but bring them back into the warmth if cold nights are forecast
  • Keep working hard to remove those weeds
  • Check for pests, particularly slugs and snails
  • Finish planting containers
  • Earth up the maincrop potatoes

An overview of May

This really is the start of serious gardening, the days are longer, the sun is getting hot but the risk of frost remains – even if frost-free it can still be cold. Remove the spent flower heads of daffodils and other bulbs growing in borders and lawns but do not cut down the leaves until they are brown.   Now is the ideal time to check stakes and ensure that plants and shrubs that need supporting are properly secured.

Keep the Weeds and Pests at Bay

As soon as the soil warms up the weeds and pests start getting serious.   Make sure beds, borders and vegetable plots are regularly hoed. Check all pots and containers regularly for signs of attack by slugs and other pests and take appropriate action. Keep an eye out for the bright red lily beetles that will become active once the temperature begins to rise. Keep checking hostas for slug and snail damage. They are these pests’ absolute favourite food.

Love Your Roses

Make absolutely sure that all dead leaves, particularly any diseased ones, are collected up and disposed of.  Do not put them on the compost heap.   It is time to spray roses against rust and black spot on their leaves.  Make sure all climbers are securely tied to their support.


Plants, particularly those that have recently been planted, must be kept moist. This also applies to any trees or shrubs that are new to your garden. If they dry out you risk losing them. Do not water beds and borders where you have recently hoed, weeds must dry out and die on the surface. Do not water in the greenhouse after early morning as this risks scorching the leaves.  Pots, hanging baskets and containers are particularly vulnerable to drying out. Towards the end of the month they should also be fed regularly using proprietary liquid or soluble feeds. Hellebors will now be flowering freely but they must be kept moist. Whilst you have the watering can or hose to hand, don’t forget to top up the pond and keep the bird bath full.

Get Some Annual Colour in Your Garden

May is the ideal time for sowing some of those faster maturing annuals and biennial plants such as nicotianas, nasturtiums, zinnias and lavateras. Keep an eye on slug and snail damage as the seeds poke their little heads through the soil. This is slug and snail fast food par excellence.

Wooden Flower Bed Border