August allows a brief respite from the frantic activity of late spring and early summer when planting out of annual flowers, dahlias and vegetable crops keeps us all busy, even more so this year given the somewhat unpredictable weather we’ve experienced.
However no gardener can afford to be too complacent.
Routine maintenance tasks now become the focus of attention; at Kelmarsh, we are being kept busy deadheading spent flowers, weeding the beds and borders and disbudding dahlias to ensure large, showy single blooms are on display for visitors to the walled garden. To ensure your container plants continue to flourish, remember to water them well and feed at least once a week with a liquid feed high in potassium (potash).
In addition to these routine jobs, now is the time to step back from your beds and borders and cast a critical eye over your herbaceous plants and shrubs. It is important to remember all plants have a natural life span, roses for example can be expected to produce a fantastic display for a number of years if well-cared for. However, after 10-12 years, many roses will need replacing and now is an ideal time to sit down with a catalogue and browse through the ever-growing numbers of new and improved cultivars available from garden centres and specialist growers.
Here at Kelmarsh, we are also busy assessing the two main borders planted with herbaceous perennial plants. Although the downpours earlier in the season held back many of the annual flowers and vegetables, the perennial plants have flourished and now is the time to identify any areas where gaps have appeared for replanting.
Some plant groups may be getting too ‘thuggish’ encroaching on neighbouring plants and should be earmarked now for dividing or digging out in the winter or early spring. Bitter experience has taught us that it’s all too easy to forget which plants you’ve mentally noted require attention so it’s a good idea to either jot such notes down on a diagram or plan of the border or, even better, stick a marker such as a short bamboo cane firmly into the ground by the plant itself.
One final task we begin towards the end of August is the propagation of frost-tender plants used in the summer containers throughout the garden. Taking cuttings is a cheap and easy way to renew stocks of many different plants and can also provide back-up supplies of those such as Penstemons which may not survive prolonged cold spells outside in the winter. Aim to collect plant material for cuttings early in the day from well-watered plants.
Simply select healthy, non-flowering shoots and cleanly cut up to 10cm of the shoot just above a bud on the parent plant. Remove the leaves from the bottom half of the cutting and trim the shoot to just below a leaf node. Dip the base of the cutting into a hormone rooting powder if you have it and insert the cuttings up to their leaves around the edge of a container filled with compost. Finish off by watering the container well to settle the compost, labelling and placing in a closed propagator case with bottom heat (around 20°C). Even if you don’t have a heated propagator, many cuttings will readily root if the container is covered with a plastic bag and placed on a warm windowsill out of direct sunlight. Remove the bag a couple of times a week to ventilate the cuttings and water if the compost has dried out then simply sit back and leave the cuttings to root. Once roots have developed, cuttings can be potted-up individually ready for growing-on and planting out next year.