Regularly deadhead winter pansies and other winter and spring flowering bedding plants to keep them flowering for longer – giving them a liquid feed will help.
Early potatoes are best sprouted (or chitted) ahead of planting next month. They will grow away quicker and give a bigger yield. Buy seed potatoes now, and set them out in boxes, trays or old egg boxes with the end containing the most ‘eyes’ uppermost and stand them in a light, airy, frost-free position.
If the weather allows and the grass is starting to grow, you may need to start mowing. Set the cutting height on your mower at its maximum and only mow when the grass is dry.
Remove any reverted green shoots on all hardy evergreen variegated shrubs to prevent reversion taking over. Feed plants to encourage good new growth.
Autumn-fruiting raspberries should be pruned now. Cut the canes right down to ground level, but leave the pruning of summer fruit varieties until after they have fruited.
Feed newly planted and established fruit trees and bushes with pelleted chicken manure. All fruit trees really benefit from a good mulch of compost or well-rotted manure.
Lily bulbs can be planted now in patio pots and borders – they’re best planted in groups of 3 or 5, in moisture-retentive, well-drained compost that is rich in organic matter.
Rake out the thatch (layer of dead grass) in the lawn to allow light, air and water through to the roots, using a spring-tine rake for small areas. You can buy very efficient electric scarifiers if you have a large lawn, or hire a powered raking machine for very large areas.
Continue planting hardy trees, shrubs, perennials and climbing plants if the weather permits. Take care when planting not to damage newly emerging spring flowering bulbs and perennial plants.
By the end of the month, prune back late summer and autumn flowering clematis (sometimes called Group 3). These include Clematis Viticella, Clematis Orientalis and large flowered hybrids such as Clematis Jackmanii. Prune all the stems back down to 25-30cms above ground level, cutting each stem back to a healthy looking bud.
Install new bird nesting boxes as soon as possible – if you get them in place now, the birds should have enough time to get used to them for nesting in this year. Place boxes in a sheltered position, facing northeast if possible and make sure they can’t be reached by cats.
Protect the early flowers and buds of camellias from frost by covering the plants with horticultural fleece, which can be purchased in rolls or as bags with a drawstring. These make life easier and quicker for putting the protection on and taking it off.
Newly emerging shoots of perennials and bulbs can be susceptible to slug attack at this time of year. Regularly inspect vulnerable plants such as hostas and delphiniums, and protect them with slug pellets, traps or nematodes.
Regularly feed indoor orchids – only use specific orchid food which can be purchased as drip feeders, aerosol spray or as a powder which you dilute.
During mild spells, check to see if patio pots and containers require watering. Top them up with new potting compost, too, and feed with a slow release fertilizer.
Cut back deciduous grasses like miscanthus, calamagrostis and pennisetum to about 15cm from ground level. Evergreen grasses such as carex and festuca can be trimmed. Cut back any dead leaves that usually collect around the base.
Prune overgrown deciduous hedges as soon as possible before the birds begin to nest. Prune the hedge 30cm lower than the height you actually want, as young shoots will quickly grow.
Here Jeff shows us how to grow large Dahlia flowers, the largest in fact. If you want a truly remarkable show this summer, these Dinnerplate Dahlias are the perfect choice. As mentioned by Jeff, these spectacular flowers were for a long time out of favour amongst the British for summer garden displays. But these days