- Grow annuals and flowering herbs which encourage
beneficial insects into your garden.
- Soil that has been flooded in previous months
will be compacted. If it has dried out sufficiently, aerate the
soil by spiking deeply with a garden fork, but take care not to
damage surviving plants or their roots.
- Keep your eyes open for pests and diseases
in the greenhouse and the garden, and take appropriate action
immediately to stop the problem getting out of hand.
- Weed regularly.
- If the weather is dry be prepared to water
new plants, seedlings and other vulnerable plants.
Be ready to protect young and vulnerable plants if frost is forecast.
- Ventilate the greenhouse and apply
shade paint towards the end of the month, and damp down if the
weather is hot
- Sow a new lawn early in the month if not
done in April.
- For established lawns you can progressively
lower the mower blade.
- Trim lawn edges each time you mow.
- If not done last month, re-cut and repair
- Apply a spring lawn fertiliser and, if necessary,
a weedkiller to established lawns.
- Alternatively treat weeds individually with
a spot weeder or dig them out with an old knife.
- Remove any coarse grasses by hand.
- Finish planting and replanting aquatic plants.
- Skim off algae
Beds & Borders
- Make a final sowing of hardy annuals,
including candytuft, clarkia, cornflowers, ornamental grasses,
larkspur, love-in-the-mist, night-scented stocks and mignonette.
- Plant out sweet peas, if not done in
- Support tall-growing hardy annuals.
- Begin to harden off half-hardy annuals
and bedding plants previously sown under glass.
- In milder areas plant half-hardy annuals
and bedding plants towards the end of the month.
- Sow biennials in nursery rows
- Plant out seedlings of Foxglove, Sweet
William, Forget-Me-Not, Wallflower, Polyanthus
- Do not plant out any tender species
until hawthorn and laburnum are blooming
- Put plant supports and stakes in position.
- Remove weak new shoots from dense-growing
perennials, such as phlox.
- In colder areas plant new perennials and
cut back evergreen ornamental grasses.
- Sow new perennials in nursery rows.
Finish planting out early-flowering chrysanthemums.
- Lift and divide spring-flowering perennials
as necessary, and trim off dead, straggly growth.
- Revitalise aubrieta, gold dust and similar
vigorous spring-flowering rock plants by cutting them back hard.
- Allow foliage of spring-flowering bulbs
to die down naturally; lift and heel them in, in an out-of-the-way
corner if you need the space.
- Stake tall-growing lilies
- Dead-head spent daffodils. Remove the
seed pod and the old petals.
- Spring feed bush and climbing roses.
Shrubs, Trees and Climbers
- Check tree ties.
- Check mulches and replace if necessary.
- Trim hedges after checking for wildlife.
- Feed container-grown shrubs and perennials
- Prune back the branches of fig trees.
Rub compost into the cut to prevent bleeding
- Clip bay trees
- Hang out pheromone traps to prevent
apples being ruined by tunnelling larvae.
- Stifle side-shoots of raspberries with pruning,
and water all soft-fruit bushes and fruit trees.
- Prune grape vines to encourage better setting
- Sow new herbs such as coriander, dill
and parsley in situ.
- Sow basil under cover
- Take cuttings of rosemary, sage and
thyme. Make them 10cm long and put them in gritty compost in a
sheltered, well-lit spot in the garden.
- Erect supports for runner beans and
climbing French beans. Make sure they will not cast shade over
plants that like the sun.
- Sow beetroot, cabbage, carrots, kale,
parsnips, peas, radish
- Begin earthing up potato plants.
- Pinch out the tops of broad beans to discourage
- Protect roots of brassicas against cabbage
root fly with artificial barriers such as card collars.
- Plant out celeriac, celery, sweetcorn, runner
beans and other strong plants grown under glass. Mulch well.
- Protect carrots against carrot fly with two-foot
barriers of fine netting or clear polythene.
- Plant fruiting vegetables under cloches.
Put up the sticky
traps for whitefly. You can't be too early with this.
In a cold greenhouse
you can now sow: basil, coriander, French beans, courgettes,
pumpkins, tomatoes (still), sweetcorn, runner beans, marrow,
gourds, parsley, lettuce, rocket
In a cold greenhouse
you can now plant out seedlings of: cucumbers, peppers, chilli,
tomatoes, rocket basil but watch the night-time temperature.
Heat to as near to 10 Celcius as you can.
Feed greenhouse tomatoes
and circubits, removing growing tips and side-shoots as necessary.