<iframe src="https://www.googletagmanager.com/ns.html?id=GTM-P46CBCM" height="0" width="0" style="display:none;visibility:hidden"></iframe>
Skip to main content
Gardening Tips for May

Gardening tips for May

The month of May brings in fresh growth and with it some new jobs to do in your garden! Trees and shrubs burst into fresh foliage and buds into flowers, cottage garden plants fill borders with new growth and container plantings are ready to be refreshed with vibrant summer colours in readiness to enjoy warmer days outdoors.

Here are some helpful tips to help you make the most of your garden in May.

Gardening Tips for May

Patio Garden

  • With the worst of the frosts hopefully behind us, May is a great month to plant your patio containers, hanging baskets and window boxes with summer bedding plants that will put on a vibrant display of colour right through until winter. During May we are fully stocked with an extensive range of quality bedding plants for you to choose from. Finding yourself short on time? Not to worry, simply choose one of our pre-planted ‘Pop Planters’, in the colour theme of your choice & simply drop into your chosen hanging basket or patio pot for a show-stopping display.
  • For best results, remember to feed containers and hanging baskets fortnightly with a liquid fertiliser, as per the manufacturer’s instructions.
  • Depending on your location, tender bedding plants including cannas and dahlias can be planted out towards the end of the month, but you should remain on alert for any late frosts and protect accordingly.
  • Bedding plants raised from seed inside should be hardened off over a period of 7 to 10 days in cooler conditions before being planting out.
Gardening Tips for May

Beds & Borders

  • Warmer temperatures will encourage weeds to burst into growth. The quickest and easiest way to control them is to hoe them off before they get a chance to get established, applying a thick layer of mulch over the soil surface to help prevent any further weeds. Mulching with organic matter, such as Bloomin Amazin, also locks in moisture and, over time, helps to improve your soil, whilst giving plants a well-needed boost.
  • Wallflowers and early spring bedding will be starting to fade now, so remove tired plantings, adding them to the compost heap, to make way for fresh summer displays.
  • Prune early spring flowering shrubs such as Chaenomeles, Forsythia and Ribes after flowering, as required. More tender late summer flowering shrubs such as Caryopteris, Perovskia and hardy Fuchsias can also be trimmed now, so they remain bushy.
  • Top dress alpines with grit or gravel to show off their spring flowers. Grit helps to prevent soil splashing on to their delicate blooms and improves drainage.
  • If hedges start to look a little shaggy, May is a good month to give them a light trim, but first check for nesting birds and, if necessary, wait until fledglings have flown.
  • Deadhead clumps of daffodils and tulips, so that energy is concentrated back into the bulb for next spring’s flowers. Leave the foliage in place to die back naturally.
Gardening Tips for May

Cottage Garden

  • In May, cottage garden plants are growing vigorously and can fill your borders with untamed growth. Plant supports should be put in place around your plants to help hold heavy stems or blooms, such as paeonies. Do this early, before your plants get too big, and the look will be more natural. We have an extensive range of quality herbaceous plants, available in-store, perfect for adding colour to existing or new borders.

  • Early season herbaceous plants, such as pulmonarias or hardy geraniums, can be cut back after flowering to encourage the re-growth of tidy, fresh new foliage and often a stunning second flush of flowers.

  • Later this month, the renowned ‘Chelsea Chop’ is also a great way to stagger height and flowering times of some of the late summer herbaceous plants. Sedums and phlox, which can sometimes grow over-tall and floppy, benefit from being cut back by one third. The resulting new growth is compact and bushy, bearing numerous, slightly smaller blooms later in the season for a prolonged period of colour.

  • You can take action to protect susceptible lush foliage plants, such as hostas, from slug damage, using granules as a physical barrier.

  • Sweet peas will be growing strongly now. Every few days, use garden twine to tie-in long growths to their bamboo or hazel stick supports. Once they are established, they will soon start to climb happily by themselves.

  • Early spring clematis montana can be cut back after flowering if required. Tie in new growth on your summer flowering clematis and honeysuckle.

  • For quick and easy results, fill gaps in borders with late sowings of hardy annuals, or plant groups of late summer flowering annuals such as cosmos or nicotiana for added colour and fragrance. Visit your local store to choose from our wide range.

  • Make sure that any new plantings are kept watered during dry spells.

Gardening Tips for May

Kitchen Garden

  • Place a layer of straw or strawberry mats under your crop of strawberries to prevent fruit being spoiled by soil splash. Net the plants, if necessary, to protect from opportunistic birds.
  • Earth up your early potatoes to prevent tubers being exposed to the light and turning green. If you have not done so already, plant main-crop potatoes now for a ready supply from late summer into the autumn.
  • Most vegetable crops can be sown now. With quick growing crops such as salads and spinach, repeat sow every 10 days to ensure a consistent supply of fresh leaves. Visit your local Dobbies to choose from our wide range of vegetable crops available in-store. Or if you prefer, we have a wide range of young vegetable plants available for quicker results.
  • Plant rows of your favourite herbs, such as parsley and coriander, for a plentiful supply perfectly suited for summer salads and alfresco barbecues. If you are short on space, grow them in containers on your patio for easy picking as you need them. Once all risk of frost is passed, grow pots of basil in a warm spot, perfect for pizzas and home-made pesto.
  • Protect young seedlings from slugs. For non-chemical control, apply nematodes to the surrounding soil as an effective organic solution or use barrier pellets.
  • Harvest stems of rhubarb and delicious asparagus spears before they grow too big so that they are tender and tasty.
Gardening Tips for May


  • Regular weekly mowing is best for an ornamental lawn, mixing the clippings into your compost heap. If you would like a wildlife lawn that will encourage birds, insects and other animals then leave the lawn to grow throughout the summer.
  • Early May is an ideal time to sow new lawns, or repair bare patches, on soil that has been prepared, levelled and firmed. Alternatively, for quicker results, lay new turf. Whichever method you choose, be sure to keep it well watered, and avoid walking on it for a few weeks to allow time for the new roots to establish.
  • To achieve a lovely green lawn, apply a high nitrogen summer feed.
Gardening Tips for May


  • Continue pricking out half-hardy and tender seedlings. When they are large enough to be planted out, be sure to harden them off in a cold frame over a period of 7 to 10 days before planting out in their final position.
  • Start to harden off tomatoes, courgettes and cucumbers, ready for planting out in June.
Gardening Tips for May

Indoor Plants

  • Cymbidiums, citrus and other foliage plants such as weeping fig benefit from being stood outside on milder days. However, beware of cold nights and bring indoors if necessary.
  • May is a great time to repot your indoor plants to invigorate their growth.