What to do during August in your garden and greenhouse.
Your monthly gardening checklists
Flowers
- Collect seeds as they ripen, from plants such as aquilegias, sweet peas and love-in-a-mist, choosing a dry day
- Deadhead dahlias and other perennials to encourage a constant display of blooms
- Keep camellias and rhododendrons well watered through late summer while their flower buds are forming
- Trim lavender once flowering is over to maintain a compact, bushy shape, but avoid cutting into old wood
- Prune rambling roses, removing up to a third of stems that have flowered, and tie the rest to supports
- Keep pots and hanging baskets flowering by watering and deadheading regularly, and add tomato feed fortnightly
- Take cuttings of woody herbs, including lavender and hyssop, choosing non-flowering shoots
- Sow hardy annuals in sunny spots to provide early summer colour next year
- Set up an automatic watering system for pots and hanging baskets if you're going away on holiday
- Strim or mow areas of wildflower meadow, now that the plants have scattered their seeds
- Take softwood cuttings from penstemons, choosing healthy, vigorous, non-flowering shoots
- Remove any spent hardy annuals if you don't want them to self-seed
- Plant autumn bulbs, such as colchicums, sternbergia and nerines, in pots and borders
On the forum: share your growing tips with other gardeners and ask for advice
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Fruit and veg
- Be vigilant for signs of tomato and potato blight, removing affected plants immediately to prevent spread
- Summer prune both free-standing and trained apple trees, to encourage good fruiting in future years
- Plant well-rooted strawberry runners into new beds
- Pinch out the tops of outdoor tomatoes, as further flowers are unlikely to produce fruits that have time to ripen
- Order saffron crocus bulbs (Crocus sativus) to plant in September, so you can harvest your own saffron this autumn
- Use netting or fleece to protect blackberries and autumn raspberries from birds
- Lift onions and shallots once their tops die down, then leave to dry in the sun
- Cut back leaves on grapevines to let the sun ripen the fruits
- Sow hardy crops such as land cress, rocket and corn salad for winter pickings
- Harvest fresh herbs to freeze in ice cubes for winter use, or to hang up and dry then store in jars
- Plant a kiwi plant, to climb over a trellis, fence or arbour
- Water crops regularly, especially during hot weather
- Plant blueberry bushes into acid soil
On the forum: which fruit and veg varieties are you growing?
Greenhouse
- Set up a capillary matting system to ensure plants have enough water if you're going away on holiday
- Plant cold-stored potato tubers in large tubs in a greenhouse or cool porch, for harvesting at Christmas
- Pour water over the greenhouse floor every morning during hot weather to increase humidity
- Plant up pots with 'Paper White' narcissus bulbs for fragrant indoor displays this Christmas
- Remove the lower leaves of cordon tomatoes up to the lowest truss, to let more light and air reach the fruits
- Take leaf cuttings from succulents, such as echeverias, crassula and sedums
- Start watering dormant cyclamen to bring them back into growth after their summer rest
- Plant flowering bulbs, such as nerines, lachenalia and veltheimia in pots indoors, for autumn and winter colour
- Look out for pests and diseases on greenhouse plants, and treat any you find immediately
- Harvest tomatoes, cucumbers and chillies regularly to encourage more fruits to form
- Tackle vine weevil infestations by watering pots with a solution of biological control nematodes
- Shade delicate plants in the greenhouse to avoid sun scorch on hot days
- Take leaf cuttings from houseplants, including begonias, African violets and Cape primroses
Fragrant Narcissus for Christmas
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Garden maintenance
- Cut laurel hedges with secateurs rather than a hedgetrimmer, to avoid half-cut leaves that turn brown
- Clear weeds from cracks in paving and driveways before they get established
- Tackle problem lawn weeds, digging them out or applying a lawn weedkiller
- Sow green manure to fill any bare ground
- Summer prune wisteria by shortening all long sideshoots to about 20cm
- Keep deadheading border plants, unless you want to collect their seeds
- Remove suckers from roses or around the base of trees
- Collect seeds and ripe seed pods from your favourite flowers and vegetables
- Prop up any clumps of tall border plants that are starting to flop, using canes and string, or twiggy sticks
- Prepare soil for sowing a lawn or laying turf during September and October
- Go on regular snail hunts, especially on damp evenings, to reduce populations
- Turn compost to speed up decomposition
On the forum: join in the discussion, share your wisdom and ask for help
Summer prune Wisteria
Visit BBC Gardeners' World Autumn Fair, at Audley End House & Gardens, Friday 2 to Sunday 4 September
£29.98
£44.97
For three 3L pots
RHS Chelsea Plant of the Year in 2011, this beautiful shrub blooms for months on end, with white flowers which have striking blue backs. Best suited to beds and borders, in full sun or partial shade.
Ends in:
£14.99
£24.99
Six jumbo plug plants
Named Plant of the Century at the 100th RHS Chelsea Flower Show, this reliable and easy to grow perennial flowers prolifically from June to October with blue, saucer-shaped blooms.
Ends in: