What to do in the garden in April

Although we know April may bring showers, there are also bright sunny days which make gardening a real pleasure. There’s more warmth in the air and colour is starting to appear to chase away the dull tones of winter. 

Trees and shrubs

Early April is the last chance before autumn for those in the south of England to plant trees and big shrubs, in order to allow time for them to get established before drier weather. For those living further north, there’s time to plant trees right up to the end of the month. If you live in a rural area and have rabbits visiting your garden, put protective wire or plastic guards around the base of any young trees planted in recent weeks. 

Check trees for signs of bracket fungus, which is an external symptom of internal rot. There is no cure for bracket fungus, so any branches affected by the fungus will need to be removed to avoid damage spreading to other parts of the tree. If you have fig trees, prune them now.

Perennials, biennials and annuals

Hardy annuals such as calendula can be sown directly in the ground now. Sow sweet peas in flowerbeds and you can look forward to a beautiful, fragrant display in early summer. Sunflowers, nasturtiums, marigolds, petunias, salvia and zinnia will all fare better if sown in the greenhouse or indoors this month. 

If you want to create a wildflower area or, if space permits, a meadow, wildflower seed can be sown in situ. April is also a good time to sow green manure crops such as comfrey if you have an area not needed immediately for vegetables. 

It’s still too early to plant out tender bedding plants, even though there are plenty on display at garden centres now. If you can’t resist the temptation to buy some this month, be sure to keep them in a greenhouse or coldframe until well into May when the risk of frost has passed. 

Trim penstemons and lavender to neaten them up before the new season’s growth. 

Vegetables and fruit

Harden off pea seedlings sown in the greenhouse in March before planting them out in shallow trenches; water them well. By the end of April you can put in pea sticks as the plants reach around 10 cm. Brassica seedlings sown in March can also be hardened off. Remember to leave plenty of space between cabbage seedlings when planting them out. Placing a collar around the stem of your cabbage plants will help to prevent cabbage root flies from laying eggs. Plant out lettuces sown in the greenhouse last month, hardening them off before doing so. Get ahead by digging trenches now ready to put plants such as celery in next month. If you ordered asparagus crowns in March, make sure you plant them as soon as possible after they arrive, while the plants are strong and healthy. 

You can now sow aubergines, beetroot, celery, French beans, parsnips, spring onions and sweet peppers. You can also make further sowings of Brussels sprouts, cabbages and cauliflowers, and sow seed potatoes, either in the ground or in tubs. Sow second earlies at the beginning of the month, spacing them 30 cm apart, and maincrop potatoes up to the end of April, allowing 40 cm between tubers. Radishes and rocket sown earlier in the year should be ready to harvest. Continue to sow radishes and rocket either fortnightly or monthly to ensure you have a regular crop throughout the summer. 

Pot-grown fruit bushes and raspberry canes should be planted by the end of April. Plant blackcurrants slightly deeper than they were in the container, but position most other types such as raspberry canes, blueberries and gooseberries at the same level in the ground as they were in the pot. Soft fruit bushes tend to be thirsty, so water them well and give plenty of water as the fruits start to develop.

Lawn care

Start to cut the lawn regularly in April, ideally once a week. If you didn’t manage to spike your lawn in March, do this now to improve drainage. Check your lawn for signs of moss and if necessary apply a moss treatment. Continue to use a lawn feed during April. April is a good time to sow a new lawn and you can also get rid of bare patches on an existing lawn with some general purpose grass seed. Neaten up any straggly lawn edges by re-cutting them, creating a small gutter at the edge of the bed to discourage grass from spreading outwards. 

Other bits and bobs

The downside of April’s warmer weather is that it encourages weed growth. It really is a case of “a stitch in time saves nine” when it comes to weeds. Spending a little time now on pulling out weeds will save you hours later in the year, when weeds are more established and the ground may be drier and harder to hoe or dig. 

If you haven’t been able to store your garden furniture inside over the winter, check for any signs of weather damage. Do the same for fencing and sheds. Repair or replace as required. A coat of wood stain will add a layer of protection to wooden furniture and fencing as well as enhancing the appearance. Metal garden furniture can easily be given a new lease of life with specialist paint designed to be applied to pre-painted furniture. Simply remove any loose paint on your furniture with a wire brush, wash it and once it is dry you can apply a fresh coat of paint. 

April is a good time to consider adding any new garden buildings, such as a shed or summer house. Constructing them now will allow you to maximise the use of them over the summer. If you need more space to plant out and sow more vegetables next month, consider adding some raised beds. They are cheap and simple to construct, and you can fill them with the ideal growing medium to get your vegetables off to a good start with all the nutrients they need. 

Planning ahead

Although April can be showery, it’s a good time to plan ahead for drier weather. Applying a layer of mulch around the base of shrubs now will help with moisture retention during dry periods in the summer. 

Order any seeds you need for sowing in May, and bedding plants to arrive in early May. This will give you time to let them acclimatise before you plant them out in the second half of May once the night time temperatures are warmer.