With climate change be prepared for very varying and warmer weather conditions in summertime in the UK. Do not be surprised by some torrential downpours and possibly extra hot days where some temporary shelter for plants may be required.
Having just returned from a lengthy tour of the tropical areas of Singapore, and very different climates of New Zealand and Australia, I was able to see the effects of a much hotter climate and past severe storms on plant life. Our temperate plants simply could not survive those conditions, so a little help and protection from gardeners in the UK summer may be required in the hottest spell to prevent unsightly leaf scorch! New Zealand is more temperate and a few parts of southern Australia. Northern Australia is very different being tropical and much hotter but with amazing ancient geological rain forest in the Darwin area.
Garden maintenance in Summer is unrelenting but easier if you do a quick tour round at the beginning of the day and make a list of all the jobs that need urgent attention.
Moisture retention Watering is needed every day as soil soon starts to dry out whether its clay or especially sandy soil. Add organic mulch (manure – compost – leaf mould) to flower beds and water retaining crystals to containers especially if you plan to be away. They can save the plant in a hot dry spell.
Lawns require a high nitrogen liquid feed for greening up after a long winter and must be watered during hot spells to avoid stress. Check your local hardware store and look for letters NPK on the fertilisers to see what you require for the plants you are growing.
Plants require a light all round liquid feed especially to prolong flowering. I recommend tomato food which is high in potash (potassium) to boost flowering and phosphorus feed to strengthen roots and stems helpful for vegetables. We forget that recent heavy winter and spring rains leach away much of the main nutrients.
Pruning especially of larger shrubs and those with suckers is vital to promote fresh growth and provide air and light particularly for other plants. Deadheading also has a big effect on prolonging flowering or the plant will start going to seed early!
Hellebore leaves take up a lot of space and light and can be safely removed to self renew in late summer. Plant out summer bedding and bulbs, hanging baskets and containers. Pelargoniums are a wise choice for containers for busy people as they are not bothered about being watered. Some rain will be sufficient.
Sow annual seeds into the ground, it’s really worth buying a packet ready prepared if time is short, and lightly cover over with soil. Add some string protection from birds but to help eliminate snails and slugs, collecting at night with a torch is very worth while if you can bear doing it with a jam jar and gloves! They love to decimate seedlings and plants especially Hostas, bedding plants and certain water loving plants such as Ligularia etc can be destroyed in days. It may help growing annual seeds in containers firstly well away from soil level if you have severe slug and snail problems.
Herbs are some of my favourite and wonderfully fragrant easy growing plants to grow also from seed. They are best grown in containers to avoid spreading. Hardy perennial herbs such as rosemary, sage and thyme are best grown in a larger container and all herbs require regular cutting, trimming and eating! I love herbs especially basil and their fragrance when you brush past.
Kitchen garden will provide regular salad vegetables so keep sowing, and plant out runner beans now. Tomatoes can be planted out but grow much better indoors under glass. Regular watering is a must for vegetables and netting protection from pigeons. Root crops will be easier to grow in a raised bed above carrot fly pest reach.
Leguminous (peas beans ) just need some manure near the roots but not rich soil as they produce their own nitrogen.
Liquid feed flowering plants, ericaceous for Rhododendrons/Azaleas, Heathers, Enkianthus – it will make a big difference.
Semi ripe cuttings can be taken now, best in mornings into a plastic bag, and important to plant quickly with hormone rooting powder.
Greenhouses should be checked for over-wintering pests, red spider mite in particular. A thorough soapy sponge-down works well as pests and many diseases hate detergents. Allow plenty of air circulation in hot days and dampening down the floor is very important. Burn any diseased material, do NOT compost.
Enjoy flaming June and those quieter garden moments!
Tony Arnold ACIHort