What to do in your garden in June

Digitalis Seeds - Pam's Split - In your garden in June

The longest day of the year is here and there’s plenty to do in your garden in June! Summer is in full swing, and the garden is growing at a rapid pace. The vegetable patch is starting to produce much anticipated harvests of tender first early potatoes and plenty of other crops come into their own this month too. See which vegetable seed to sow in June, and check out our June flower seeds for summer and autumn blooms.


Flowering plants in June

  • Sow Peruvian lilies (alstroemeria), achillea, Canterbury bells, arabis, coreopsis, erigeron, forget-me-not (myosotis), and Sweet William seeds in their flowering positions.
  • Sow polyanthus, primrose, and pansy seeds in the greenhouse for autumn planting and flowers in spring.
  • In early June, apply general purpose organic fertiliser to beds prior to planting out summer bedding plants.
  • Thin out hardy annual seedlings as they emerge from last month’s direct sowings. Keep the strongest and largest seedlings, removing the weaker ones to give the remaining plants plenty of room to develop.
  • June is an ideal time to raise foliage plants like coleus and the sensitive plant (Mimosa pudica) from seed for enjoyment indoors. Indoor plants, like begonia ‘Escargot’, are ideal for brightening indoor spaces too.
  • If you have any spare bedding plants left over, use them to create colourful container displays to move around the garden as required. When planting, debud/deflower the plants to encourage them to focus on growing a better root system and establish quicker.
  • Pinch out the shoot tips of bedding and perennial plants to make a bushier plant develop. More stems will lead to more flowers.
  • Fertilise your rose plants to encourage strong growth and good flower production. Use granular feed and sprinkle around the roots. If it doesn’t rain during the first week or two gently water in or use a hoe, being careful not to harm the roots.
  • Remove dead foliage from spring flowering bulbs, with the exception of daffodils and tulips which should be left to die back naturally. Do, however, take off any seed-heads that appear.
  • Lilies grown in pots will be growing quickly at this stage of the season, and the developing flowers will need some form of support. Keep an eye on lilies in your borders too, if they’re not close to neighbouring plants.
  • Plant rooted chrysanthemum cuttings and hardened-off summer-bedding plants into their final flowering positions.

Vegetables in June

  • Pinch the side shoots from your tomato plants. Gently twist off the shoots that sprout from the joint between the main stem and the fruit-bearing branches.
  • Plant out greenhouse raised or bought vegetable plants now. This includes Brussels sprout, cabbage, celery, courgette, cucumber, marrow, runner and French bean plants.
  • Thin out rows of beetroot, carrot and lettuce seedlings, removing any small and weak ones. Continue making staggered sowings for a longer harvesting period.
  • Hand pollinate pumpkin, courgette, and marrow plants to encourage a good fruit set. Use a paintbrush or your finger to transfer pollen between any open flowers.
  • Protect carrots from carrot fly and cabbages from caterpillar damage by covering with fine mesh netting.
  • Take care not to damage your early potato tubers as you start to harvest. Use a long handled fork to gently loosen the soil and pick up any tubers that you see.
  • Keep the greenhouse well ventilated during the day to reduce temperature fluctuations. Keeping doors and windows open all day will also allow pollinating insects and predators of aphids and greenfly to benefit your greenhouse plants.
  • Apply a high-potash liquid tomato feed to cucumbers, sweet and spicy chilli peppers and aubergines.

Fruit in June

  • Inspect your fruit plants and trees for pests.
  • As the current season’s raspberries and blackberries canes grow tall, tie them in to support wires. Remember that summer fruiting raspberries produce fruit from the previous year’s canes and autumn fruiting plants on the current year’s fresh growth.
  • Use a fruit cage or netting to protect soft fruit bushes like currants and strawberries from birds (especially blackbirds) as the fruit ripens.
  • Uncover any fruit crops growing under glass or cloches to allow access for pollinating insects.
  • Keep greenhouse doors open during the day to allow indoor strawberries to be pollinated by insects.

Pots, baskets and containers in June

  • Plant young patio plants in troughs and containers to make beautiful flower displays for the front of your home.
  • Take hanging baskets out of their sheltered spot and place in their final position.
  • Order a pre-planted hanging display if you haven’t planted up your own yet.
  • Remember when planting your container displays, leave a small gap between the top of the compost and the top of the container pot or hanging basket, so that any excess water will be absorbed rather than spilling out.

June lawn care

  • Mow the lawn regularly as growth speeds up this month. Lower the cutting height for established lawns and make sure to water newly seeded grass during dry spells.
  • If you haven’t already had the opportunity, apply spring/summer lawn fertiliser to established lawns.

General June garden jobs

  • Install shade netting or blinds in the greenhouse to block out some of the sun’s rays and lower the temperature. Alternatively, apply shading paint to the glass.
  • Ventilate polytunnels this month by propping doors open during the day.

June pond care

  • Keep an eye on your pond fish to ensure they’re healthy.
  • Keep the pond clear of algae so the water remains oxygenated and clear.
  • Remove blanket weed using a rake or cane. Leave it at the edge of the pond for a day or two to allow any wildlife to escape, before adding it to the compost heap.
  • Check any new pond plants before planting to avoid accidentally introducing pests like snails.
Lead image: Digitalis Seeds – Pam’s Split from Suttons
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