Posted by Shannen Godwin on 17th Jun 2021
Gardening Jobs for May
May is one of the busiest months of the year, filled with planting jobs, maintenance and plenty all around preparation to make sure your garden is ready for summer! For a garden you’ll love spending all your time in over the next few months, here are our experts’ must-do garden jobs for May.
What to plant in May
Plant your bulbs outdoors.
Whether you’ve already started potting up your bulbs, or you’re planting them straight into the ground, you can plant out all of your bulbs this month! Bulbs like Dahlias and Cannas can be planted out as soon as the last risk of frost has passed, so keep your eyes on the weather forecast near you before you start planting.
Plant up hanging baskets.
Continue to plant up your seasonal hanging baskets for weeks of versatile colour. Fill baskets with well-draining, multi-purpose compost and plant your bedding plants within. If you’ve been growing rapid plugs or maxi plugs in a greenhouse or indoors, these can be planted in hanging baskets as soon as they are established and have a strong root system, but keep baskets in a greenhouse or porch for a couple of weeks to let them establish before they go outside.
Alternatively, when your garden-ready plugs arrive, these can go straight into your baskets and can be hung outdoors straight away.
Plant out summer bedding and annuals.
Like bulbs, you can plant our summer bedding and tender annual plants when the last frosts have passed. This includes sunflowers, cosmos and nasturtiums - move them from the greenhouse to your beds, borders or containers as soon as you can!
Plant potted plants outdoors.
Wondering what plants to plant in May? By now you probably have plenty of potted perennials or shrubs, whether you’ve shopped online or treated yourself at the garden centre. May is the ideal time to plant your pot-grown plants straight into the garden - in beds, borders or containers.
Some advice from the experts: when you remove your potted plants from the pots they arrived in, make sure you tease the roots. Simply put your gardening gloves on and pull the roots apart at the bottom of the plant, being careful not to snap or damage them. When the teased plants are planted, their roots will expand more naturally and ensure your plants can get the water and nutrients they need for a healthy summer of growth.
Have you seen our NEW range of Large Format Pots? We’ve introduced a range of your favourite perennials and shrubs, now available in larger pots. Add instant impact to your garden this year with these great value nursery plants, grown in J. Parker’s nursery in Lincolnshire.
Garden jobs in May
Harden off tender plants.
If you’ve potted up tender plants indoors, you can start to harden these off before planting outdoors. Planting tender plants outdoors too soon, without hardening them off, can shock your plants - hardening off ensures a smooth transition into the garden.
Day by day, start to move your tender plants (like Dahlias) outdoors and leave their pots in the garden throughout the day. In the evening, bring your plants back indoors, leave overnight, and repeat the process for a minimum of two weeks. By then, the frost will have passed and plants can safely go outside
Prune spring shrubs.
When shrubs like Forsythia have finished flowering, prune spent flowers with a pair of sharp secateurs. This will help keep them neat and compact, to ensure they don’t get too leggy or unruly when they flower again.
Support climbing plants.
Climbing plants like Clematis, Honeysuckle and Wisteria will all be getting new shoots after the winter dormancy. When spotted, make sure to tie all new shoots to supports like trellises or wires to make sure they grow to the shape/look you desire.
Feed spring-flowering bulbs.
By now your garden should be filled with spring blooms like Tulips and beautiful Daffodils. To ensure the best displays next year and more high-performing bulbs, use liquid feed to give your bulbs the nutrients and energy they need. Do this and you’ll notice just how many more flowers you spot next year!
Tidy spring bedding.
Have your spring annual plants been and gone? Remove faded flowers like wallflowers to make space for your new summer bedding. You can even add these to your compost bins - make sure they don’t go to waste.
Be cautious of scarlet lily beetles.
If you’ve grown Lilies or Fritillaria, you’ll want to keep a close eye on their foliage for scarlet lily beetles. These pests can very quickly destroy your plant's foliage, especially at this time of year, but luckily now is the perfect time to stop any infestations before they begin.
Check all your plants for small red beetles and remove them from foliage as soon as you see any. It’s easy to lose them when you spot them, so a lot of gardeners tend to lie newspaper paper under plants to catch them, and quickly crush them before they get back on your Lilies.
Pinch out new bedding shoots.
When you spot new shoots on your bedding plants, pinch them out (as you would Dahlias) with your fingernails, at the next set of leaves down. Your bedding plants will quickly produce multiple new shoots for every shoot pinched out, so it’s a great way to get bigger, bushier blooms.
Take cuttings of woody herbs.
Take cuttings from woody herbs like hyssop, thyme and rosemary now. Use a pair of secateurs to cut small cuttings off your plants, and root them in a gritter compost. Leave them to grow in a greenhouse or on a warm windowsill, and you’ll have new young plants for free in no time.
What vegetables to plant in May
Sow sweetcorn seeds in deep pots.
If you want to plant sweetcorn this year, you can start sowing them in deep pots now! Sow sweet corn, one seed per pot, in deep pots, and leave to germinate in a greenhouse or a warm windowsill. You can then plant these sweetcorn pots out into the garden in June.
Sow French beans and runner beans outdoors.
Dwarf and climbing varieties of French and runner beans can be sown directly outdoors now. Beans like warm weather, so start sowing seeds on a nice sunny week, to give them all the warmth and light they’ll need for productive, healthy crops.
Continue to sow salad leaves.
Rocket and salad leaves can also be sown directly outdoors now, commonly in trenches or beds. You can get continuous crops of salad leaves by sowing new seeds every 2 weeks, making sure to label each variety as you go. By harvest time, you will get continuous new salads ready to eat for weeks.
Bulbs to plant outdoors now
Dahlias.
Our all-time favourite bulbs, Dahlias are a staple flower of any summer garden. We recommend mixing and matching a range of Dahlias like the gorgeous dinner plate varieties, unique cactus dahlias, and the subtle, neat yet beautiful pompom dahlias. You can shop our expert-curated Dahlia Mixtures for stunning colour schemes guaranteed to perform.
Cannas.
Another summer favourite, Cannas are a statement bloom you definitely won’t miss! Their beautiful tropical look is guaranteed to make a statement in any border or pot, with their warm-toned petals and huge, decorated foliage. If you’ve never grown Canna rhizomes, now’s the time to start!
Flowers to plant in May:
Salvia Large Flowered Collection
Plants that flower in May:
Growing Guides for April
Dahlias | Begonias | Gladioli | Zantedeschia