Perhaps more than any other month it’s a good idea to keep a close eye on the weather during April.
Frosts are still common, and many plants and flowers may need protection in the form of fleece or cloches. Hopefully, the ground will not be too wet and so now is a good time to finish off digging over your plot in preparation for all the vegetables you are going to grow.
As the weather gets warmer, the weeds will grow in earnest.
So a mantra for the month is regular weeding, before they take over...
Ready, steady, sow
As soon as the ground reaches 6°C you can start to sow salad, beetroot and annual herbs, such as dill and rocket. The same goes for hardy annuals, such as larkspur, nigella or seed mixes. If your soil still feels cold lay fleece directly over freshly sown seed to hold in the heat.
Continue to sow seed of half-hardy annuals under cover. Sow in small pots rather than trays to save space, and prick out after the first leaf is fully formed. A pinch of anything as fine as salt will be enough for most gardens, but larger seed such as ipomoea, tagetes and squash can be sown in pairs in 10cm pots. Never handle seedlings by the stem when pricking out. To avoid damage, gently grasp the first set of primary leaves.
Evergreens, such as rosemary, lavender, bay, myrtle, sage and thyme, can be pruned as soon as the winter is over. Never cut into old wood and always leave enough foliage to help draw energy back into the limbs.
Potatoes and onions
Plant out seed potatoes once ‘chitted’. Grow half a dozen in a dustbin if you have room in the greenhouse for a plate of earlies. Line out then just plunge onion sets and shallots into ground that has been firmed and raked. They like soil that's been manured the previous year.
Get your lawn in shape
After a winter of neglect, your lawn will benefit from a bit of tender love and care now. Start mowing once a week, beginning with the blades at the highest setting and gradually lowering them over the weeks.
For a perfect finish, trim the lawn’s edges with long-handled shears or a grass trimmer. Bare or thin patches of grass can be thickened up by raking over the surface and then resowing. Lastly, give the lawn a feed. If it contains weeds or moss, treat these at the same time with a weed, feed and mosskiller treatment.
If you are turfing, this is the perfect time to do so. Work from boards to tap the sods gently into place and spread your weight. Stagger the joints as you would bricks in a wall. If the weather is dry you may need to water to prevent curling at the edges. Feed established lawns with a slow-release organic fertiliser high in nitrogen to get things off to a good start.
Plant out sweet peas
After pinching out sweet peas last month, they should have strong side-shoots that will flower well. Plant them next to a support that they can climb by wrapping their tendrils around; they’ll need to be tied in with string at the start to get them going.
Bed of roses
Foliage-feed the first new growth on the roses and continue to do so every three to four weeks to avoid the use of toxic rose sprays. A rose ‘tonic’ from your garden centre will help to ward off blackspot and mildew which will be lying dormant and ready to pounce. A handful of slow-release organic blood, fish and bone spread evenly about the roots will set up the health of your plants.
Start an asparagus bed
Early April is not too late to start an asparagus bed. Make sure the ground is prepared ready for the arrival of the asparagus crowns as you will need to plant them shortly after they arrive. The crowns must not be allowed to dry out.
Clean up your strawberry beds or pots
Remove any dead or damaged leaves and old runners from the plants. If the plants are getting older, thin out the smaller crowns leaving three to four crowns per plant. Apply a fresh layer of straw if using as a mulch.
All soft fruits, such as strawberries, raspberries, redcurrants, blackcurrants, and gooseberries will benefit from a mulch. Garden compost, leaf mould, organic manure, straw, hay and spent mushroom compost can all be used. Hay is more beneficial than straw as it breaks down more easily and releases more nutrients into the soil.
Apply an acidic mulch to blueberries and cranberries. These are acid loving plants, so mulch with an 8cm (3in) layer of acidic material such as bark or old pine needles – kept from your Christmas tree!
- Feed bare soil between plants with general-purpose fertiliser and dose acid-loving rhododendrons and camellias with sequestered iron.
- Prune the flowered shoots of hydrangeas and winter jasmine.
- Sow peas, broad beans, brassicas, leeks, root veg, spinach, chicory, Swiss chard, salad and hardy herbs.
- Pinch-out fuchsia, sweet peas and pelargoniums to encourage bushiness and heavier flowering.
- Deadhead daffodils and tulips as the flowers finish but leave the foliage intact allowing it to die back naturally.
- Divide hostas before they come into leaf.
- Plant out strawberry beds, making sure you enrich the soil first with plenty of well-rotted manure. Place cloches over your strawberry plants for earlier crops.
- Mulch fruit trees with well rotted manure or garden compost taking care not to mound mulch up around the trunk.