Garden Jottings for May
Once again, as last year, Spring has arrived about 3 weeks earlier than is normal. What a truly mixed month April proved to be with record-breaking hot days preceding cold ones with night frosts followed by strong gale force winds. Unpredictable weather really is a problem for the unsuspecting gardener. Unfortunately the unusual weather overwhelmed the daffodils which just withered and dried up too soon. Tulips, which should be at their very best late in April and through May, have mostly been and gone while all the ornamental cherry trees have given a marvellous explosion of blossom and colour everywhere – not successional as usual, but all at once!
Thankfully a little recent rainfall has helped to ease the plight of struggling border plants and we have more seasonally normal temperatures which are easier to work with. So, after the beautiful blooms of early Spring have faded it is time to prune forsythia and other early flowering shrubs, taking out one or two of the oldest stems and pruning back to a nice compact shape. Feed rhododendrons and azaleas with ericaceous fertiliser.
Hydrangeas can have some colourant powder watered in round the soil at the base of the bush to enhance or alter the colour of the blooms. Give these plants and peonies some feed to encourage strong growth and large blooms. Feed roses, if not done last month, and apply a spray against black spot and aphid infestation. Always spray on a still quiet evening when bees are less in evidence.
Plant out dahlias and chrysanthemums, making sure they have been hardened off well, keeping an eye out for slugs which love any new young shoots. Cut off any remaining seed heads on daffodils and tulips, leaving the stems and leaves to die back naturally to feed the bulbs for next year. Harden off hanging baskets you have previously planted up by placing them outdoors during the day and back indoors at night until they’re fully acclimatised and can be hung up in their final positions. This practice should be followed for any tender plants that have been inside where it is warmer than outside.
Rockeries should be at their best just now but keep dead heading and clip over to prolong flowering. Any gaps can be planted up with mesembryanthemums, sweet alyssum, bedding begonias, pansies and dwarf dianthus. Keep snow in Summer and dwarf ornamental nettles under control as they can swamp more delicate and attractive plants.
As spring gives way to summer, wallflowers, double daisies and polyanthus will need to be replaced with antirrhinums, ageratums and other bedding plants you may have grown. Polyanthus can be planted in a shady corner with some leaf mould or compost added. When planting, these plants can be split up and replanted in the autumn but don’t forget to water them in dry periods. Pansies you have removed can also be utilised in old spots and rockeries after cutting back and tidying the plants.
Keep all new plants, seedlings and soft fruit well-watered. Rather than little and often, a good soak less often is more beneficial as the water goes deeper into the soil and therefore the roots.
Sow spinach, carrots, lettuce and radishes again now for a continuation of cropping. Plant out dwarf French beans after all danger of frost is past; also runner beans a little later on. Grow these up between poles or on cane wigwams. Keep these beans tied in to start them climbing up supports and water them well, preferably in the evenings when water soaks in better. It aids fertilisation of the flowers if they are sprayed lightly with water at the same time.
Potatoes should be earthed up to keep them and their new shooting leaves free from frost, making a ridge over the row. Plant main crop potatoes now to harvest in September and October. Sow radishes, spring onions and coriander which will be ready to harvest in a couple of months.
Weed onions by hand to avoid infection by onion fly by keeping the scent of the onions from attracting the pest. Place straw around strawberry plants as they begin to produce fruits as this will keep them clean and dry. Make sure to net the bed. Netting can be stretched over hoops or upturned pots on top of canes. Always anchor these nets securely. These cages are useful to protect brassicas from pigeons and butterflies though they need to be considerably larger and taller.
Keep indoor tomatoes growing on steadily moving up only to a slightly larger pot one size at a time and give a high potash feed. Remove side shoots as they appear and tie the plant onto the cane. Outdoor tomatoes must be carefully hardened off keeping fleece at the ready in case of a chilly spell. Herbs should be growing strongly now and can be split up if they are too large and straggly; give them a trim and pot on adding sharp sand or grit to aid drainage to the compost.
Ventilate green houses and cold frames. Carefully pot up cuttings of geraniums, fuchsias and white marguerites to make good strong plants for pots and borders next month. Plant up dahlias, adding a cane as you plant to avoid piercing the tuber if you add it later.
Place supports round herbaceous plants before they need to be tied up, adding canes or twigs tied in securely around the plants as the plants grow up. There is nothing worse than trying to prop up plants that have flopped over or broken in bad weather – prevention is better than cure!
On a drizzly day, if it’s warm enough, give house plants a shower to clean the leaves. Even hairy leaves will benefit from a shower but not heavy rain which can damage leaves. Smooth leaves can benefit from wiping with a little milk to give a shine. It it is a good idea to replace the top couple of inches of soil with some fresh compost and add a top dressing of grit if liked.
Check ponds and maybe purchase new plants such as irises or marsh marigolds, rushes and arum lilies. If it is at all possible try to have a bog garden at one end to encourage toads, frogs and other invertebrates and insects, all of which enhance the garden and help to keep down slugs and bugs. If the area is planted up with ferns, grasses and astilbes it will give cover to wildlife and a safe area for birds to bathe and drink.
Keep bird feeders and tables cleaned to avoid the spread of avian diseases.
Hoping for some much-needed rain to moisten the soil and prepare for planting out and sowing annual seeds and being able to apply lawn feed and even some seed on bare worn patches. This time of year is so enjoyable as the daylight hours lengthen giving more time in the garden at this busy season.
Look out for seeds of biennial sweet williams and foxgloves for example as they will need to be sown later in June to be ready to plant out and make sturdy plants to flower in the border next year.
Enjoy your garden.
Christine Brown,
President, Ash Horticultural Society