GARDENING TIPS FOR MAY
The month of May doesn’t just bring new jobs to do in the garden - it’s an exciting month with lots of fresh growth and plants to enjoy. Beautiful blooms begin to open, meaning bright new colours to admire. Trees and shrubs burst into leaf. Containers are ready to be refreshed with vibrant bedding plants in readiness to make the most of warmer days outdoors. Safe to say summer is officially on its way!
Alongside new plants to fill your outdoor spaces with, May will hopefully bring some consistently warmer weather to make gardening this month even more rewarding. After fighting through frosts and April showers, the gradual transition from spring to summer is a great motivator to get outside and tackle those gardening tasks that you maybe weren’t able to get to during the earlier months of the year
From bedding to seed sowing, we've pulled together some handy tips to help you make the most of your garden in May
Our gardening expert's top tips:
Once you’re certain there won’t be any more frosty mornings or nights, you can start mowing your grass as usual - about once a week. Follow our guide on getting your lawns summer ready for more tips and tricks
On warmer days, remember to ventilate your greenhouse vents and doors to help regulate the temperature and humidity levels, which encourages healthy plants
Make sure you check for nesting wildlife before clipping hedges, mowing long grass and pruning shrubs
THIS MONTH IS ALL ABOUT: SUMMER BEDDING
May is THE month to plant your summer bedding plants. From busy lizzies (Impatiens) to begonias to petunias, bedding plants can cover every area and fill every gap in your garden. Plant your favourite flowers in your patio containers, hanging baskets, window boxes, beds and borders for a vibrant display of colour right through summer
Finding yourself short on time? Not to worry - choose one of our pre-planted ‘Pop Planters’, in the colour theme of your choice and simply drop it into your chosen hanging basket or patio pot for a show-stopping display
SEEDS TO SOW IN MAY:
FLOWERS
Cornflowers (last chance to sow)
Sunflowers
Zinnias
Primrose
Wallflowers
Pansies
Daisies
FRUIT & VEGETABLES
Cucumber
Main crop carrots
Broccoli
Swede
Beetroot
Peas
Spring onions
French and runner beans
Sweetcorn
Courgettes
Pumpkins
MAY LAWN CARE
Regular weekly mowing is best for a perfect summer lawn. You can mix any grass clippings into your compost heap or bins if you have them too
Top dress any alpines you’ve planted last month with grit or gravel to show off their spring flowers. Grit helps to prevent soil splashing on to their delicate blooms and improves drainage
Depending on your location and weather, tender plants including cannas and dahlias can be planted out towards the end of the month - just remain on alert for any late frosts and protect accordingly
Roses, peonies, and gladiolus are some of the best flowers to plant in May. Roses and peonies will fill your garden with sweet summer fragrances, while gladiolus is ideal for adding to your cut flower bouquets
FLOWERS TO PLANT AND GROW IN MAY
Take action to protect susceptible lush foliage plants, such as hostas, from slug damage using granules as a physical barrier
Sweet peas should be growing strongly now. Every few days, use garden twine to tie-in long growths to their bamboo or hazel stick supports. Once they’re established, they’ll start to climb happily by themselves
For quick and easy results, fill gaps in your 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
Our bedding plant of the month, geraniums (Pelargoniums), are popular amongst avid gardeners as they provide a boost of colour throughout summer and are easy to grow and maintain. Plant geraniums in bedding displays or in pots – they look particularly beautiful growing beside lavender
WHAT TO DO WITH BEDS & BORDERS
Any bedding plants you’ve raised from seed indoors can be hardened off over a period of 7 to 10 days in cooler conditions before being planted outside
For a lovely green lawn, apply a high nitrogen summer feed
Early May is an ideal time to sow new lawns or repair bare patches on soil that has been prepared, levelled and firmed. Make sure to keep it well watered and avoid walking on it for a few weeks to allow time for the new roots to establish
WHAT TO PLANT IN POTS & CONTAINERS
Bedding plants are versatile and can be used to brighten up outdoor pots, troughs, window boxes and hanging baskets – pick your favourites and start potting-up!
Any permanent plants in your pots and containers should be top-dressed with mulch and compost – this gives them the organic matter they need to grow their best
There's still time to plant lavender in containers in May if you haven’t done so already. Planting lavender in containers means you can move it around your garden wherever and whenever you’d like - sit it next to a doorway or wherever it will catch a light summer breeze, so its rich floral scents are carried through your garden and home
Remember to feed containers and hanging baskets fortnightly with a liquid fertiliser - particularly your spring flowering bulbs that will still have life left, like tulips
MAY FRUIT & VEG
Begin to plant strawberry runner plants in outdoor beds, hanging baskets or pots, but only if the weather is warm enough. Net the plants, if necessary, to protect them from opportunistic birds
If you’ve been germinating tomato seeds you can plant these outside from early may, as long as frosts have passed
Earth up your early potatoes to prevent tubers being exposed to the light and turning green – earthing up just means continuing to cover up shoots with soil as they grow. If you have not done so already, plant main-crop potatoes this month for a ready-to-harvest supply from late summer into the autumn
Most vegetable crops can also 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
Plant rows of your favourite herbs, such as parsley and coriander, for a plentiful supply perfectly suited for summer salads and al fresco barbecues. If you’re short on space, grow herbs in containers on your patio, balcony, or windowsill for easy picking as you need them. Grow pots of basil in a warm spot for all your summer pizza parties
Later in the month you can harvest any previously planted stems of rhubarb and asparagus spears at their tastiest and most tender. You can also harvest any grown lettuce, radishes or rocket
MAINTAIN TREES & SHRUBS
Hydrangeas are our hardy plants of the month – plant them in May and come next month, you’ll have delicate flowers in shades of pink, white, and even blue
If your hedges are looking a little shaggy, May is a good month to give them a light trim - but first check for nesting birds
Prune early spring flowering shrubs such as Chaenomeles, Forsythia and Ribes after flowering
More tender late summer flowering shrubs such as Caryopteris, Perovskia and hardy Fuchsias can also be trimmed now so they remain bushy and full of life all season
INDOOR GARDENING
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 outside in their final position
Start to harden off tomatoes, courgettes and cucumbers too, ready for planting out in June
Cymbidiums, citrus and other foliage plants such as weeping fig benefit from being placed 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
If you’re looking for some exotic new indoor greenery, our houseplant of the month the Ficus (also known as a rubber plant) is a popular choice for tropical plant lovers. They make eye-catching, long-lasting additions to rooms with lots of sunshine and warmth
GENERAL MAINTENANCE
Deadhead clumps of daffodils and tulips so that energy is concentrated back into the bulb for next spring’s flowering. Leave the foliage in place to die back naturally
Wallflowers and early spring bedding will be starting to fade now, so remove tired plantings to make way for fresh summer displays - add them to your compost heaps and bins for homemade compost
Make sure that any new plants are kept watered during dry spells
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
Warmer temperatures will encourage weeds to burst into growth. The quickest and easiest way to control them is to hoe them off before they have the chance to become established. Applying a thick layer of mulch over the soil surface helps prevent any further weeds from growing. Mulching with organic matter also locks in moisture and, over time, helps to improve your soil, whilst giving plants a well-needed boost
In May, cottage garden plants are growing vigorously and can fill your outdoors with untamed growth. Plant supports should be put in place around your plants to help hold heavy stems or blooms of flowers such as paeonies. Do this early, before your plants get too big, and the look will be more natural
Protect young seedlings from slugs. For non-chemical control, apply nematodes to the surrounding soil as an effective organic solution, use barrier pellets
LOOK AFTER WILDLIFE
Hang birdfeeders in your trees and clean bird baths so any birds visiting your garden have access to food and water
Continuing planting, or if you haven’t started planting already, flowers for pollinators, such as coneflowers, lavender and various other wildflowers
Why not have a go at creating a bee bath for an environmentally friendly feature in your garden? It’s super easy to make – all you need are some terracotta pots and planters, plus some small rocks – and it provides bees easy access to water to keep them healthy and busy
If you would like a wildlife lawn that encourages birds, insects and other animals to visit, then leave your grasses to grow longer throughout the summer
We would love to see what you get up to in the garden this April, take a picture and tag us on socials with @dobbiesgardencentres for your chance to be featured on our social media channels