With decent rainfall last month, ending a largely dry start to the summer, any plant growth retarded due to a lack of water will have made up for lost time by having a late spurt of new, soft, foliage. This makes the usual task of ‘editing’ borders, by removing excess growth where it threatens to collapse, or where it is smothering neighbouring plants, even more important in August.
There will also be a rash of new weeds to remove especially where weeds which ran to seed quickly, during the hot spell, have spawned a new generation of seedlings. These will be desperate to produce a whole new generation of offspring before cooler autumn temperatures halt their ability to set seed. Gardening is a constant ‘plate spinning’ act whereby there is always some task which is becoming wobbly, i.e. critical, just as you get on top of another one.
Pests may also be making good use of the flush of new plant growth, after the rains, so continued vigilance in this area is another plate that needs to be kept spinning. I had thought that there were relatively few lily beetles around this year, I assume there was a spell of cold weather in the winter which must have coincided with a point where the overwintering adults were at their most vulnerable, but removing their filthy, poo encrusted, grubs from lilies is a timely way of breaking their life cycle and reducing the number that are able to overwinter.
Lush new growth is also particularly susceptible to fungal diseases so removing leaves and stems which are exhibiting dieback, infected foliage, or are simply too lax, will help to keep plants healthy. Avoid using nitrogen rich fertilisers at this time of year, especially on lawns, because the ‘soft’ growth that this promotes is particularly likely to succumb to disease.
In a similar vein, it is a good idea to prune and trim, removing flowered stems and growth down to a point just above where they originate from, Mediterranean style shrubs and sub-shrubs—lavender is a prime candidate. ‘Tightening up’ these, often silver-leaved, plants means that they have a chance to relocate themselves in new shoots which have time to harden up before the onset of winter.
Lavender is particularly prone to becoming ‘leggy’ if not treated to this late season trim and that’s a shame because it is an indispensable constituent of many gardens, especially welcome due to its ability to attract nectar loving insects. Without a bit of well-timed maintenance it can be a short-lived shrub, quickly becoming a straggly mess, but, if regularly trimmed back after flowering, lavender can survive to a ripe old age.
As ever there are certain tasks, which you will have been doing all summer, which need to continue if your garden is not going to ‘run out of steam’. Watering, feeding and dead-heading summer bedding displays and half-hardy perennials, in tubs and containers, is still important. If you are going on holiday soak all these thoroughly and try to find a reliable person to keep them watered during any dry spells. It’s probably too much to ask for a friendly neighbour to do your dead-heading as well, so plan to remove all the flowers, and the coming buds too, on any bedding plants that would otherwise go to seed in your absence.
I mentioned last month that taking cuttings is a good idea because the hormone levels that promote good rooting are at their highest; continue taking cuttings into August and keep an eye on those already taken for signs that they have successfully rooted. Seed sowing is another easy form of plant propagation; half-hardy plants can be sown now to produce early flowering plants to plant out in early spring. Some of the most popular ‘cottage garden’ type plants fall into this category; annual poppies (Papaver), Californian poppies (Eschsholzia), English marigolds (Calendula), larkspur or annual delphinium (Consolida) etc.
Collecting seed from garden flowers is the other side to the coin and now is a good time to gather up suitable candidates (generally the same sort of plants as those listed above for timely sowing!). Collect when they are bone dry, anything damp or wet will simply rot unless sown immeadiatly, and store in paper bags or envelopes rather than in plastic bags or sealed containers. Seed is also a good way of spreading the gardening love around because you can pass it on to other gardeners or, a la Ellen Willmott, scatter it yourself in their gardens when you visit—this a also a good way to test how good they are at weeding.
Ellen Willmott (1858-1934) was a renowned gardener during the heyday of English gardening in the late Victorian and early C20th period. It is reputed that she broadcast the seed of the silver, spiky, eryngium, Eryngium giganteum, into the borders of gardens that she visited so that it would germinate, establish and then, appearing from nowhere, spring up in those gardens in future years. This may, or may not, be true but, in honour of this story, this silvery perennial is commonly known as ‘Miss. Willmott’s Ghost’.
Today, with all the ‘rewilding’ that’s going on, as seen recently during the ‘NGS’ opening of the glorious ‘Slape Manor’, Netherbury, and also on a visit to the pioneering ‘Knepp Castle Estate’ in Sussex, I think I might choose to scatter the seed of ‘Yellow Rattle’ (Rhinanthus minor) as my ‘ghost’ of choice.
It is sown, absolutely fresh, into ares of established grass if you want to reduce the vigour of that grass as the first step to creating a ‘wildflower meadow’. Rattle seed ripens from late June to August, the seedheads making the characteristic rattling sound when mature, and it is imperative that it is harvested before all the seed is shed and then sown, without delay, into the grass where you hope to get it established.
I find that yellow rattle is only really able to get established if the receiving grass sward is mown, preferably ‘scalped’, and some scarification performed, either by vigorous raking or using a powered scarifier. I’ve successfully performed this with a Stihl ‘Kombi’ cultivator attachment, although something like a ‘Mantis’ tiller should also manage the necessary loosening of the soil surface.
Rattle needs to have a winter of exposure to low temperatures, ‘vernalisation’, in order to break its dormancy and successfully germinate the following spring. It is used in the ‘rewilding’ of established lawns, or other grass monocultures, because it is semi-parasitic of grass species and thus weakens existing perennial grasses thereby allowing the less vigorous wildflower species, plus finer grasses, to re-emerge from the existing seed bank (or allow introduced wildflower mixes to get a foothold). It’s less of a ‘ghost’, more of a hidden assassin, a ‘meadow-making ninja’, but certainly a plant most fitting to the ever-changing style of English gardening.
