Tips for May

Trees and Shrubs

It is still an ideal time to plant shrubs. Dull showery weather is most suitable, so long as the soil is not “sticky”. Farmyard manure can be added to improve the soil. Any acid loving plant requires ericaceous compost.

Pot grown shrubs are most ideal for planting as the roots do not get damaged. It is better to plant as soon as possible to enable the new roots to have as much time as possible to establish themselves before the end of the growing season.

Young Arbutus, Ceanothus, Choisya, Fuchsia and Hydrangea’s can be a little tender, so these are best planted out in the second half of the month. Protect them on frosty nights with protection fleece.

After planting, water the shrubs and then mulch with decorative chipped bark. If there is a dry spell after planting is may be necessary to water again.

Faded flowers need removing from Rhododendrons, Azaleas and Camellias. The plants may now be cut back as far as the old wood (do not cut into old wood) and then fed with an ericaceous feed.

Forsythia and other spring flowering shrubs, e.g. Viburnum bodantense Dawn need to be given a hard prune straight after flowering.

Climbers and Wall Plants

Train new growth into place using twist wire. Early flowering Clematis are best left with little or no pruning, however if these are out-growing the space, they can be pruned back to 3 buds as soon as flowering has finished. Clematis that flower twice a year are best left un-pruned.

If May brings a dry spell, water the climbers as the soil at the base of walls can quickly dry out.

Roses

Keep a watch for aphids attacking new growth - at the first signs spray with Provado Ultimate Bug Killer.

Also watch for black spot and mildew – at the first signs of these, spray with Dithane.

Spraying is best carried out in the evenings.

Inward growing shoots need to be removed to allow air circulation around the plant and this will also help reduce the risk of disease.

Beds and Borders

Frequent hoeing and hand weeding is needed to keep “on top of” the growth of weeds.

Protect young shoots from slugs by sprinkling slug pellets around the base of the plants. Organic slug pellets are also available at our garden centre (this is also preferable if you have any pets).

Top-dress with a light layer of farmyard manure and hoe in slightly to give a feed to the beds and borders.

Place suitable supports for tall growing perennials.

Bulbs and Corms

Remove dead flower heads from Daffodils, Hyacinths and Tulips.

Dahlia tubers can be planted now.

Rock Gardens and Ponds

Vacant places in the rock garden may still be planted with pot grown plants. Aubretia needs to be trimmed back to keep them tidy and compact.

It is the ideal time to plant new aquatic plants and to divide established plants.

Lawns

Weather permitting grass should be now cut at least once a week.

Supergreen Moss Killer and Lawn Tonic can be applied if this has not already been carried out.

Apply a lawn weed killer if needed.

Fruit

Remove surplus raspberry shoots, leaving only the strongest and give plants a good mulch of decorative chipped bark.

Spray tree and soft fruit against pest and diseases (Provado Ultimate Bug Killer).

Be careful not to spray on open blooms as pollinating insects may be killed.

Vegetables

Main crop potatoes not yet planted must be put in as soon as possible. Early potatoes may be “earthed up”.

Continue to make sowings of Lettuce, Raddish, Beet, Carrots and Peas - to extend the cropping season.

Runner and French Beans may be sown, along with Spinach, Swede and later in the month Sweetcorn.

Brussels Sprouts, Cabbage and Celery may be planted out when they have been “hardened off”.

Greenhouse and Frame

More ventilation will be needed on hot sunny days and shading may need to be installed. More frequent watering will be necessary.

Tomatoes making new growth need to be securely supported, any side shoots appearing need to be removed as soon as they appear.

House Plants

Plants standing on sunny windowsills should be removed from the mid-day glare. Give water as necessary and add bio liquid feed at half the recommended strength approximately every two weeks.