Bask in the summer sun
Here are your June gardening jobs with added links if I have more information on the subject. May’s jobs are mostly still relevant if you’ve fallen behind or if the weather’s been bad.
Week 1
Sow salad crops, such as beetroot, Chinese cabbage, pak choi and radish. Leafy salads do better when sown in light shade.
Sow runner, French and broad beans, peas, squash, sweetcorn, and outdoor cucumbers directly into prepared beds.
Open doors and vents on greenhouses to increase ventilation. Damp down the floor to increase humidity. Give plants a liquid feed.
Plant out hardened-off summer bedding and seed-raised plants. Keep well watered in and moist during dry weather.
Fill gaps in herbaceous borders with hardy annual bedding, such as Calendula, Godetia, and Clarkia.
Lift clumps of forget me not once the display wanes, and before plants release too many seeds.
Liquid feed container plants every two to four weeks.
Sweet peas need training and tying into their supports to encourage them to climb and make a good display.
Continue to protect lily, delphiniums, hostas, and other susceptible plants from slugs and snails.
Prune overcrowded, dead or diseased stems of Clematis montana once it has finished flowering. It will take cutting back hard.
Although most winter brassicas need to be sown earlier in the season, calabrese, turnips, and kohl rabi can be sown now for an autumn crop.
One of the most vital June gardening jobs is starting to treat potatoes and tomatoes against blight.
Plant out celeriac and celery.
June gardening jobs – Week 2
Inspect lilies for red lily beetle and crush them.
Runner beans need well-prepared ground and suitable supports for the shoots to twine around and grow upwards.
Don’t forget to give greenhouse plants more space as they put on new growth.
Perennials such as hollyhocks, delphiniums and lupins can be sown directly into drills outside.
Stake tall perennials to prevent wind damage to flower spikes.
Tie in climbing and rambling roses as near to horizontal as possible. This will encourage side shoots to grow along the length of the stem, for more flowers.
In wet areas, plant container trees and shrubs.
Ward off carrot fly by covering plants with a fine woven plastic mesh like Enviromesh.
Net cherries against birds, keep protection in place for all soft fruit.
Week 3
To grow spring bedding for next year, sow wallflowers, pansies, and Bellis perennis from now until next month. Winter bedding can also be sown.
Cut back dead bulb foliage if not done already. Wait until the foliage dies down naturally.
Rhododendrons can be lightly pruned after flowering. More severe pruning should wait until the following early spring.
Thin out new shoots on trees and shrubs that were pruned in winter to stimulate growth. Remove crossing stems.
Vine weevil larvae can be a serious pest of container plants and are active now. There are various biological controls available.
Take softwood cuttings of many deciduous shrubs, including Fuchsia, Hydrangea macrophylla, Philadelphus and Spiraea.
Ensure newly planted trees and shrubs do not dry out. Water with rain, grey or recycled water.
Shorten newly planted raspberry canes once new shoots are produced.
Water blueberries, cranberries and lingonberries regularly with rainwater.
Peas need staking with pea sticks, netting or pruned garden twigs.
June gardening jobs – Week 4
Thin pears, plums, peaches, nectarines, apricots and apples.
Keep tubs, hanging baskets and alpine troughs well watered. Use rainwater, or recycled grey water.
Cut back clumps of spring-flowering perennials to encourage a fresh flush of foliage.
Euphorbias look better if spent flowers are removed, cutting the flowered stems back to ground level and it discourages powdery mildew.
Perennials that are showing new shoots from the crown can still be propagated via basal stem cuttings.
Take cuttings from garden pinks (Dianthus). Pull off the parent plant while holding a non-flowering shoot four pairs of leaves from the tip. Treat as softwood cuttings.
Remove early aphid infestations by hand, as they can transmit viruses.
Clip evergreen hedges such as privet, box, and Lonicera nitida if needed. Prune out frost damage.
Prune wall-trained Pyracantha, removing shoots coming out from the wall and shortening other new growth to about 8cm (3in).
Prune deciduous magnolias once in full leaf. If this is done in winter, when the tree is dormant, dieback can occur.
In ponds, remove blanket and duckweed. Don’t introduce goldfish into wildlife ponds.
Regularly inspect plants, and greenhouse structures, for red spider mites, whitefly, thrips and other pests.
One of the most important June gardening jobs is pruning flowering shrubs such as Deutzia, Weigela and Philadelphus after they have finished flowering.
Gaps between winter brassica plants can be used for radishes or lettuce.
Summer prune red and white currants and gooseberries.
Pinch out the top of broad beans once the lowest flowers have set to prevent aphid attack.
Water tomatoes and peppers regularly to prevent blossom end rot.
For gardening jobs in July, visit my week-by-week page. To catch up on May’s jobs, see here.
June gardening jobs updated June 2022