Early summer in the organic garden is full of colourful new growth. This makes a busy - but lovely - month in the garden. Keep on top of weeds and remember the two organic principles: good soil management, and diverse planting to encourage plenty of beneficial wildlife.
Soil and composting 🔗
- Add a mulch on any bare, moist soil, using compost. Organic mulches keep soil moist, and deter weed growth (remove weeds before mulching). Mulches provide a safe habitat for all sorts of beneficial creatures, such as centipedes and beetles that devour slugs and other pests. And the compost provides a constant source of nutrients.
- Keep adding to your compost bin, making sure to mix 'greens' (lawn cuttings etc), with 'browns' (cardboard, straw and scrumpled up paper). Turn the heap to aerate it, add water if it feels dry and dusty. See Home Composting.
- See Managing your soil and the members factsheet, Managing your soil.
- If your first sowings and plantings have failed or are unhealthy there is still time to sow some more. Soil will have warmed up and direct sowings should be more successful.
- Hoe off weeds before they flower/set seed. Seedlings can be left to shrivel and die on the soil surface. Put larger ones in the compost heap (without seed heads.)
- Harvest comfrey leaves to make your own liquid feed for tomatoes and other container grown plants. See Comfrey.
- Fill any empty gaps still awaiting vegetables with a fast-growing cover crop of green manures. Buckwheat, mustard, phacelia or trefoil can all still be sown if the ground is moist enough. See Green Manures or the members factsheet on Green Manures.
Pest and Disease Watch
- Grow plenty of predator-attracting flowers, to bring in the beneficial creatures such as parasitic wasps, ladybirds and hoverflies.
- Use fleece or fine mesh to protect brassicas against caterpillars, particularly the colonies of large cabbage white butterflies.
Also against leek moth and allium leaf mining fly. See Pests and Diseases for treatment, or the members factsheets Leek moth and Allium leaf miner.
- Cut chard regularly to protect it from the leaf miner (a tiny fly that lays its eggs on the underside of the leaves, creating brown blotches).
- Pull up and compost courgette plants suffering from cucumber virus. Their leaves are stunted, fruits are small, and the plants will not recover. There is still time to sow a variety, such as Defender, that has some resistance to this disease.
- Tomato leaves may turn yellow, curl up, go purple underneath, develop brown patches or other oddities. This is not disastrous, it's due to fluctuations in day and night temperatures. Keep plants watered consistently to avoid blossom end rot. This is particularly important for tomatoes growing in pots and grow-bags. Use a liquid comfrey feed once the first truss has set.
- Squish heavy infestations of aphids on fresh plant shoots with your fingers (wear rubber gloves if squeamish). Avoid sprays - as birds, wasps and other beneficial creatures are feeding their young.
- Unless a wasp nest is in a really inconvenient and potentially dangerous location, it need not be destroyed.
- Apply a seaweed-extract foliar spray which contains natural growth stimulants and a variety of trace elements. Besides improving the quality of your fruit, the plants become stronger and healthier so are less susceptible to pest and disease attack. Available from The Organic Gardening Catalogue.
- Water newly planted fruit trees/bushes, and keep a weed-free area around their bases to reduce competition for water and nutrients.
- Most top fruit and soft fruit will benefit from some pruning and fruit thinning. For more information on specific crops refer to our Fruit Growing Manual.
Pest & Disease Watch
- Inspect strawberry fruits regularly for grey mould (Botrytis cinerea), removing any that are infected. Ensure plenty of air circulates around the plants and keep fruit off the soil by putting a straw mulch underneath.
- Check gooseberry bushes regularly (daily if possible) for gooseberry sawfly larvae. Look first in the centre of the bush, but wherever you see half-eaten leaves, larvae will be present. Pick off and destroy.
- Check apple trees for silver grey powdery mildew; cut out any infected shoots and leaves.
- Speckled leaves with a fine webbing on the surface and underneath in apple and plum trees indicates fruit tree red spider mite. Pick off and destroy as many leaves as possible, but on large trees this isn't practical.
- Plant attractant flowers near fruit trees to increase predators - such as hoverflies - who will feed on the mites.
- Continue hanging up codling moth and plum fruit moth traps. Codling moth larvae tunnel into small fruits, spoiling a lot of the flesh
- Check Pests and Diseases for further help and information. Also the members' factsheets Gooseberry sawfly; Attracting beneficial insects; Apple powdery mildew; Pear midge and leaf blister mite; Aphids; Codling moth.
- There is still time to sow and grow your own organic herbs, such as borage, chives, fennel, summer and winter savory.
- Herbs are superb attractant plants when in flower. They bring bees and a huge range of beneficial insects into the garden.
- Mint rust (orange blobs on leaves and stems) can continue from year to year. Remove and destroy plants and start again with new stock.
- Chive rust is less serious and temporary. Cut plants back to stumps; fresh clean growth will re-grow rapidly.
- Mulch bare soil, making sure it is moist first. Mulches retain water and suppress weeds. Use a thick layer of last autumn's leaves, several layers of newspaper covered with grass clippings or even composted wood chippings.
- Hoe off weeds before they flower/set seed. Seedlings can be left to shrivel and die on the soil surface. Put larger ones in the compost heap without seed heads.
- Dig out bindweed on sight. This nuisance weed hates disturbance, and will eventually give up as long as you can dig it out as soon as it sprouts. Its roots, and others from pernicious weeds such as dandelions, docks and ground elder, can be put in a bucket of water (or black plastic sack) and 'drowned' for at least 3 months. Then put the nutritious sludgy mess on the compost heap.
- Top dress all plants growing in containers. Scrape off the top 4cm/2” of compost, and replace with a 50/50 mixture of fresh potting compost (peat-free and organic if possible) and your home-produced garden compost. Use a liquid feed for hanging baskets.
Keeping the growing area healthy 🔗
- Leaf spots, rusts and rose blackspot are rarely killer diseases; they just disfigure. Remove affected leaves, flowers and berries and put in the green waste bin for professional composting.
- Avoid sprays, even organic ones, as they also target the predators such as hoverflies, ladybirds and parasitic wasps. Squash large aphid colonies with your fingers – wear gloves if squeamish.
- June is a good month to use biological pest controls. These are available online. Biological controls from The Organic Gardening Catalogue. They require 18-20°C for a couple of hours a day, so make sure you can achieve these temperatures before you buy. Avoid using any sprays for at least a week before introducing biological controls.
- Brown marks on plants' leaves in the greenhouse are often caused by sun scorch. Take care to water plants from below, and install shading of some sort.
- Provide sheltering plants close to the pond so that water-loving wildlife can climb in and out without exposure.
- The pond itself needs two-thirds of its surface covered by plants of some sort to keep algae at bay. See members' fact sheet Setting up a pond.
Lawns and hedges
- Frog and hedgehog alert! Before cutting into any damp overgrown grass, go round with a stick and see what can be chased out of these sheltered spots.
- To use the nutrient rich worm casts on your lawn, either wash them into the grass using a watering can, or wait until they dry out completely, and just brush into the grass.
- Only mow where needed. Allow other areas to grow and let attractive grasses flower - providing insect homes and habitat for egg-laying butterflies. Long grass can be cut back at the end of the season, and added to the compost bin.
- In areas where grass is sparse and difficult to grow, dig it well in and plant a ground-covering plant instead such as ajuga (Ajuga reptans, common name ‘Bugle”) in shady areas under trees.
- Trim back hedges, but take care not to disturb birds and fledgling chicks. Feed hedges after cutting. A mulch of grass mowings at the base of the hedge provides some valuable nitrogen.
- Continue to water and feed plants regularly. Leafy plants require a feed rich in nitrogen (N), while flowering plants need potash (K).
- Sooty mould grows on honeydew excreted by aphids. The mould itself is relatively harmless unless photosynthesis is severely disrupted. Wash the leaves and deal with the pests. See Pests and Diseases.
- Hoover up whitefly and sciarid fly on indoor plants. Set the hoover on gentle, shake the plant then suck the pests up as they fly.