What to do during April in your garden and greenhouse.
Your monthly gardening checklists
Flowers
- Sow hardy annuals, such as love-in-a-mist and pot marigolds, as well as native wildflowers, into gaps in borders
- Enjoy instant colour by planting primulas and polyanthus in pots and at the front of borders
- Protect the new shoots of hostas, delphiniums, lupins and other vulnerable plants from slugs and snails
- Continue deadheading spring bulbs and bedding, so they don't waste energy setting seed
- Plant pineapple lily (eucomis) bulbs in pots for exotic-looking summer flowers
- Sow sweet peas at the base of supports, and transplant those sown in autumn into their final positions
- Spray the new leaves of disease-prone roses with fungicide to control mildew, rust and blackspot
- Take basal cuttings from clumps of perennials, such as delphiniums, campanulas and lupins
- Prune hydrangeas, cutting back the old stems to a healthy shoot lower down
- Reinvigorate mature clumps of hardy perennials, such as hostas, asters and daylilies, by dividing and replanting
- Sow sunflowers in a sunny, open site, then water regularly and protect seedlings from slugs and snails
- Check for aphids on roses and rub them off before they develop into major infestations
- Add aquatic plants, such as waterlilies and irises, to garden ponds
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Fruit and veg
- Plant second-early and maincrop potatoes
- Place cardboard collars around the stems of brassicas to deter cabbage root fly from laying their eggs
- Pinch out the tips of broad beans if they're covered in aphids, or spray shoots with soap-based solution
- Sow outdoor varieties of tomatoes, chillies and courgettes in pots, so they're ready to plant out in late May or June
- Divide clumps of hardy herbs, such as lemon balm and chives, then replant in pots, borders or a dedicated herb bed
- Sow small batches of rocket and other easy salad leaves
- Continue planting bare-root asparagus crowns and Jerusalem artichoke tubers
- Sow flowering companions in the veg plot, such as pot marigolds and borage
- Continue planting batches of garlic, shallots and onions every few weeks to extend the cropping period
- Sow herbs such as parsley, coriander, dill and chamomile in a sunny bed or container
- Protect emerging seedlings from slugs and snails
- Sow fast-growing crops, such as radishes, to make the most of any temporary gaps
Greenhouse
- Prick out seedlings growing in pots and trays as soon as they produce their first true leaves
- Sow sweet peas in deep pots and keep them frost-free in a greenhouse or on a sunny windowsill
- Start feeding houseplants once a week with liquid fertiliser, continuing through to autumn
- Sow quick-growing microgreens, such as kale and mustard, for nutrient-rich pickings in just a few weeks
- Transplant greenhouse tomatoes into growing bags or large containers and tie in the stems to supports
- Plant up hanging baskets and pots with summer bedding, but keep indoors until after the last frost
- Sow herbs in pots or trays, including basil, chives, parsley, fennel and coriander
- Thin out heavy fruit sets on peaches and nectarines, leaving fruits about 10cm apart
- Sow runner beans, French beans, cucumbers, courgettes, pumpkins and sweetcorn in pots
- Pinch out the shoot tips of fuchsias to develop bushier plants
- Attach guttering to the greenhouse and install a water butt, so you can make good use of April showers
- Clean greenhouse glazing to let in as much light as possible
- Maintain good plant hygiene, picking off faded blooms and dead leaves before fungal diseases can take hold
- Open greenhouse doors and vents on warm days, or install automatic vent openers, to improve air circulation
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Garden maintenance
- Put a bag of barley straw in ponds to discourage algae and keep the water clear all summer
- Lay turf or sow grass seed to create a new lawn or repair damaged patches
- Cut back tatty old fern fronds to make way for new ones that are starting to unfurl
- Keep cloches or large sheets of fleece handy to protect young plants if late frost is forecast
- Cut away unwanted suckers growing around the base of trees and shrubs
- Hoe between rows of veg seedlings regularly, as weeds grow rapidly at this time of year
- Remove moss and weeds in turf, and boost growth with a nitrogen-rich lawn feed
- Check that guttering on sheds and greenhouses is clear of debris, so that April showers will fill up water butts
- Add new aquatic plants to ponds and divide established plants that have outgrown their baskets
- Put pumps and fountains back into ponds, thoroughly cleaning the filters first
- Treat problem weeds, such as nettles and brambles
- Look out for clusters of aphids on shoot tips and young leaves, and wipe off before they multiply
- Keep putting out food for birds, as they're busy raising their broods
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Enjoy an exclusive day out on 20 September, 2018, travelling by luxurious, private train from London to Chatsworth, one of England's finest stately homes. Guests will receive gourmet food hampers and a free goody bag, with tickets costing £385pp.
Offer Ends:
Visit the beautiful Isles of Scilly and Tresco Abbey Gardens on a four-day trip on 13-16 October, 2018. Enjoy a talk and Q&A session on Mediterranean planting, and a garden tour from Tresco Abbey Garden's Mike Nelhams.
Offer Ends: