June jobs and tips for your garden
June 21st is the longest day of the year, and the extra light and warmth encourages the garden to put on an exuberant burst of growth. But this extra light and warmth also means weeds will sprout up from seemingly nowhere. Keep on top of them by hoeing regularly in dry conditions.
• Hoe borders regularly to keep down weeds.
• Be water-wise, especially in drought-affected areas.
• Water your containers and baskets well in hot weather. Start to feed them with a balanced fertiliser every 2
to 4 weeks.
• To conserve water, water the soil rather than the plants and make ponds around individual plants so that
the water can really soak in, ideally wetting the soil quite deeply, say to 25cm (10in). Thorough watering like
this supports plants for 14 days, but merely wetting the surface wastes water, encourages weeds and can
lead to surface rooting making the plants more vulnerable.
• Use water butts as much as you can to water your plants, it is a good idea to try to use water from the
water butts for the next few month.
• Keep an eye out for white powdery mildew on plants. If possible, remove the affected parts and spray with
a fungicide to prevent further spread, always check this whilst the weather is warm and throughout the next
few month make it part of your checks every so often.
• Look for aphids on the underside of leaves - rub them off by hand or spray with an insecticide to prevent
them multiplying. Alternatively try using a natural pest control such as Lacewing larvae. This is another
thing to keep an eye on throughout the next few months.
• Keep an eye out for scarlet lily beetles on your lilies - remove and crush any you see. Also check for the
sticky brown larvae on the underside of leaves.
• Check for vine weevils by tipping your plants out of their pots and looking for 'C' shaped creamy maggots
amongst the roots. Treat with nematodes if vine weevils are spotted, keep an eye on this throughout the
warm weather and over the next few month.
• Clip evergreen hedges such as Privet, Box and Yew whilst they are in active growth.
• Turn the compost in your compost bins every month to keep it well aerated.
• Keep bird baths topped up in hot weather, continue to do this throughout the summer months until
Flowers and Bulbs:
• Prune many spring-flowering shrubs.
• Position summer hanging baskets and containers outside.
• Plant out annual summer bedding plants now.
• Plant up containers, hanging baskets and planters now the risk of frost has passed. If you have them
growing on in a greenhouse move them outside to their final position.
• Continue to thin out drifts of hardy annuals if they're overcrowded.
• Lift and divide clumps of snowdrops and bluebells once the leaves start to yellow. Also do this with
overcrowded clumps of bulbs.
• Keep newly planted trees and shrubs well-watered whilst they establish.
• Now there is space on windowsills again, think about sowing biennials for next year.
• It's not too late to sow seeds of annual plants.
• Pinch out the tips of your Fuchsias to encourage a bushy habit and more flowers.
• If any of your hanging basket plants have become leggy or misshapen, simply trim the excess off - this will
encourage bushy growth.
• As soon as your sweet peas start to flower, keep picking them to encourage more blooms.
• Dead-head your roses if they are repeat-flowering types. Otherwise leave the seed heads on for
• Dead-head and cut back oriental poppies after flowering. Cutting them close to ground level will stimulate
• Stake tall or floppy plants and perennial plants to prevent wind damage.
• Towards the end of June, if your hardy Geraniums have finished flowering cut them back to encourage
new foliage and flowers.
• Cut back bulb foliage as soon as it has died down naturally.
• As new shoots grow, tie in and train climbing plants such as honeysuckle and clematis to their supports.
Use Soft-Tie Wrap for a secure tie.
• Prune out overcrowded or dead stems of evergreen Clematis such as Clematis armandii after it has
finished flowering to maintain a good shape.
• Harvest flower heads from your lavender plants to use in baking or as a garnish to your meals!
• Sowings can now be made outdoors of alstroemeria, achillea, arabis, canterbury bells, coreopsis, erigeron,
myosotis and sweet william seeds.
• Sow in the greenhouse polyanthus, primrose and pansy for autumn planting to flower in spring.
• In early June apply general purpose-pelleted organic fertiliser prior to planting out summer bedding plants.
• Thin out hardy annuals sown direct in their flowering positions.
• Plants in the home are always popular and June is an ideal time to raise foliage plants such as coleus and
the sensitive plant (mimosa pudica).
• To brighten up winter and spring displays indoors, make sowings of calceolaria, cineraria and primula
• Although it will be some time before they flower, sow cactus and the amazing strelitzia seed.
•If you have any spare bedding plants left over such as celosia, begonia, geranium or impatiens (busy lizzie)
pot them up to provide a colourful display in a light porch or on a windowsill, to provide colour throughout
• To encourage strong growth along with a good flower display sprinkle rose fertiliser around the roots.
• Remove any dead foliage from spring flowering bulbs, with the exception of daffodils and tulips which could
be left a little longer but do take off any seed-heads that may appear. However, if possible, it is best to allow
the foliage to naturally die back.
• Lilies that are in pots will be growing quickly at this stage of the season, with the flowers starting to
develop, and could very well need a few canes for support. Lilies in garden borders may also need to be
supported if they are not close to neighbouring plants.
• The danger of frost will have now hopefully passed, and young bedding plants that have been grown on
under protection during spring can be planted outdoors ready for those beautiful displays, or into summer
hanging baskets and containers.
• When using containers or hanging baskets remember not to fill them right up to the top with compost but
leave a small gap so that when watering it will soak in and not run over the edges.
• It will also prove very beneficial to give your potted plants a weekly liquid feed to improve growth and
• When planting out debud/ deflower the plants as this will encourage them to grow a better root system and
produce the required flowers.
• A number of young plants would also benefit by having their shoot tips pinched out which encourages
•By pinching out the shoot tips bushier plants develop along with more stems leading to more flowers.
• Harvest lettuce, radish, other salads and early potatoes.
• Charlotte and Maris Peer potatoes can be planted from mid-June to late July. These are best planted into
our 40 litre patio bags, 5 tubers per bag. No chitting is necessary as the warmth of the compost and the
summer temperatures will quickly entice growth. Keep the compost moist at all times whilst the plants are
growing, do not overwater or saturate the compost as this can compact the compost and squeeze out the
oxygen, preventing the developing tubers from swelling. Also container growing allows them to be moved
into your greenhouse or shed if blight threatens.
• Pinch out any side shoots from your tomato plants and feed once the first truss is setting fruit. You can pot
up the side-shoots to create new tomato plants.
• Continue to earth up potato plants as they grow. If you're growing potatoes in bags simply add more
compost to half way up the plant stem.
• Harvest salad crops and resow every 2 weeks for a constant supply of tasty leaves.
• Harvest early potatoes - these are normally ready from 10 weeks after planting.
• Look out for onion and garlic leaves yellowing and dying back - this means they are ready to harvest!
• Plant out tender vegetables such as courgettes , squash, tomatoes and sweet corn now the risk of frost
• When planting out cabbages, use cabbage collars to prevent cabbage root fly attack.
• There is still time to plant runner beans - sow them directly in the ground now.
• Plant out greenhouse raised Brussels sprouts, cabbage, celery, courgettes, cucumbers, marrows, runner
and French beans.
• Beetroot, carrots and lettuce rows can be thinned out and further sowings can be continued.
• Remember smaller crops will be produced when over-crowded sowings are made, and any unwanted
seedlings should be carefully removed.
• In the case of pumpkins, courgettes and marrows hand pollinate to encourage good fruit set.
• Protect carrots from carrot fly and cabbages from caterpillar damage by covering the crop with
Envirofleece or Enviromesh.
•When digging up early potatoes take care not to pierce or damage the tubers.
• Start to prune your plum or cherry trees now.
• Although fruit trees will naturally shed some fruit (called the 'June drop'), aim to thin out congested
branches further for bigger and better fruits.
• Protect any developing fruits from birds and squirrels by placing netting around your plants.
• If you have plants fruiting in containers, make sure you give them a high potash liquid feed to keep plants
healthy and productive.
• Top-dress patio dwarf fruit trees with fresh compost and a slow-release fertiliser.
• Peg down runners on your strawberry plants to create more plants for next year. If you don't need more
plants simply remove the strawberry runners completely.
• Inspect fruit bushes and trees for pest and diseases, and treat as necessary.
• As new canes of raspberries and blackberries appear, tie to support wires but remember to keep them
away from last year’s growth as this will flower and fruit this summer.
• It is a good idea to either use a fruit cage or drape netting over soft fruit bushes such as currants, as well
as strawberries which are either growing in rows or containers, to prevent birds, especially blackbirds, from
stripping unprotected plants of their fruit.
• Strawberry crops that have been kept under glass, cloches or fleece should now be uncovered so that
pollinating insects can gain access. Also if strawberries are being grown in a greenhouse open doors fully
• Mow lawns at least once a week.
• If you are experiencing prolonged dry weather, set your mower blades higher to reduce stress on the
• Water your lawn during hot weather, particularly newly seeded or turfed lawns. Do not allow new lawns to
• Warm weather encourages rapid weed growth - apply specific lawn weed killer to tackle this problem.
• Feed your lawn with a special lawn fertiliser to encourage healthy green growth.
• Recut any lawn edges if needed do this as and when needed throughout the next few months. Try
installing lawn edging to make future maintenance easier.
• Keep the greenhouse well ventilated during the day as temperature fluctuations caused by quite hot
temperatures in the day, then going cool at night could very well affect tomato plants fruiting. Also tapping
the flowers of greenhouse tomatoes will improve pollination.
• Shade greenhouses to keep them cool and prevent scorch, using shade netting or a shading paint.
• Rooted chrysanthemum cuttings and summer-bedding plants that have been hardened off in the
greenhouse can be planted into their flowering places.
• Don’t let plants wilt so remember to water them regularly.
• A weekly feed with a high-potash liquid tomato feed should be given to cucumbers, capsicums and
• Harden off half-hardy bedding plants to acclimatise them to outdoor conditions.
• Continue pricking out and potting on seedlings and cuttings.
• Plant glasshouse tomatoes in beds or growing bags.
• Damp down your greenhouse on hot days to increase humidity and deter red spider mites.
•Hang fly traps throughout the greenhouse to monitor levels of whitefly, thrips and other pests.