Home Gardening jobs May gardening jobs

May gardening jobs

Get out and enjoy yourself!

Here are your gardening jobs for the month – with added links if I have more information on the subject. Last month’s tasks are all still relevant to do now if you’ve fallen behind or if the weather’s been bad. For the ideas behind how and when we do gardening tasks, visit the Gardening Jobs page.

Week 1

If you’re seduced by ready-planted hanging baskets at the garden centre, make sure they’re properly hardened off – same with trays of annuals and veg.

Cover emerging shoots of potatoes with soil. If the tubers are exposed to light, they turn green because of an increase in chlorophyll, which makes them have a high level of glycoalkaloid toxins.

Aquilegia Green Apples May gardening jobs
Aquilegia Green Apples

In the veg garden, sow quick-growing crops, such as salads, between longer-term residents, such as brassicas.

Mulching fruit crops will help them to retain moisture around the roots.

Take softwood cuttings of deciduous shrubs, including Forsythia, Fuchsia, Hydrangea macrophylla, Philadelphus and Spiraea – choose non-flowering stems.

Rose James L Austin, May 29 May gardening jobs
Rose James L Austin

For roses, remove weeds and water during dry spells. Check roses for signs of black-spot, aphids and leaf-rolling sawfly damage, treat if required.

Collect rainwater in barrels.

Trim winter-flowering heathers with shears.

Daffodil Sweetness, May 1 May gardening jobs
Daffodil Sweetness, May 1

Keep nipping off the dead flower heads of late-flowering daffodils and let the foliage die down naturally.

After flowering, dig up and divide Primulas.

Tall-growing plants such as Delphinium, Lupin and monkshood need a framework of canes and string around them. Do this now so the supports become unobtrusive.

Tulips Triumph Mix, May 1 May gardening jobs
Tulips Triumph Mix, May 1

When old tulips have finished flowering, discard the bulbs, ready to plant up containers with summer bedding.

Give shrubs, trees, and borders a mulch of compost, to preserve water and smother any weed seedlings.


May gardening jobs – Week 2

Harden off tender plants by leaving them outside for increasing periods of time, building up to overnight exposure for a fortnight.

Hosta Canadian Blue May gardening jobs
Hosta Canadian Blue

Divide clumps of herbaceous perennials. Bamboos and clumps of bulbs or rhizomes can be divided in the same way.

Thin out direct sowings of hardy annuals and vegetables, in two or three stages at fortnightly intervals.

Remove faded wallflowers and spring bedding, to make space for summer plantings.

Pulmonaria Ocupol May gardening jobs
Pulmonaria Ocupol

Cutting back clumps of spring-flowering perennials such as Pulmonaria and Doronicum can encourage a fresh flush of foliage.

Lift and divide overcrowded clumps of daffodils after flowering. Deadhead tulips and daffodils. Apply a liquid fertiliser to bulbs after they have flowered. Allow foliage to die down naturally.

Inspect lilies for red lily beetles – they’re extremely destructive and active now.

Adult red lily beetle May gardening jobs
Adult red lily beetle

Protect carrots with insect-proof mesh to prevent carrot root fly.

Liquid feed fruit trees growing in pots with a balanced feed every fortnight.


Week 3

Sow cauliflower, purple sprouting broccoli, and winter bedding plants.

Broccoli May gardening jobs
Purple sprouting broccoli

Spreading and trailing plants such as Alyssum and Aubrieta, can become tatty, so trim them back after flowering.

Put supports in place for herbaceous plants for those like peonies that produce heavy blooms.

Lift clumps of forget-me-not once the display wanes, and before too many seeds are released.

Helianthus Lemon Queen with bee, Sept 8
Helianthus Lemon Queen with guest

Pinch out leading shoots on plants such as Chrysanthemum and Helianthus to encourage bushy plants.

Pot on root-bound plants.

Tie in climbing and rambling roses as near to horizontal as possible, to restrict sap flow, causing more side-shoots to grow along the stem, producing more flowers.

Potato Jazzy in 8l bags
Potato Jazzy in 8l bags

Earth up potatoes when the shoots are 23cm (9in) high, in order to prevent the new tubers going green, leaving 5cm (2in) of shoot uncovered so that the plant has enough foliage to continue growing.

Put netting in place to protect all soft fruit from birds.


May gardening jobs – Week 4

Hoe borders to prevent annual and perennial weeds from spreading and seeding themselves.

Chaenomeles Jet Trail
Chaenomeles Jet Trail won’t be swamped by the ornamental rhubarb any more

Sweet peas need training and tying into their supports to encourage them to climb and make a good display.

Liquid feed plants in containers every two to four weeks. This will keep them healthy and blooming until the first frosts hit your garden.

Aphids can multiply rapidly. Remove early infestations by hand to prevent the problem getting out of hand. Protect sweet pea plants in particular, as they can get sweet pea viruses.

Hosta snails
Hosta after a severe attack by snails

Protect lilies, delphiniums, hostas, and other susceptible plants from slugs and snails.

Prune spring-flowering shrubs such as Japanese quince (Chaenomeles), Choisya and Ribes after flowering. Evergreens such as Viburnum tinus can also still be trimmed.

Prune wall-trained Pyracantha, removing any shoots coming out from the wall, and shortening other new growth to about 8cm (3in). This encourages spur formation and increases flowering.

Red Pyracantha berries
Red Pyracantha berries

Remove blanket weed in ponds by twirling around a rough stick. Skim off floating weeds such as duckweed with a net. Leave weeds on the pond side for 24 hours to allow trapped creatures to return to the water.

To catch up on April gardening jobs, visit my week-by-week page here. To get ahead, read June’s gardening jobs here.

May gardening jobs updated June 2022