The Garden in August by Keith Cowley
Perhaps surprisingly for many gardeners August is not a favourite month. Possibly this is because in most years by August lawns can be looking rather brown and parched which seems to detract from the rest of the garden. Possibly it is because the spring and early summer flowers are over or that weed growth and pests and diseases can seem to be overwhelming the garden. For others it may be the work involved in getting the garden ready prior to going away on holiday and then on the return to find that the beds are overgrown and the lawn badly in need of a cut!
Having said all this August still has much to offer the gardener. It is the final month of summer and as such is the last month of strong plant growth, there are also many flowering plants which are at their best in late summer and the vegetable and fruit garden will be in full production. Colour and interest in the garden at this time of year can come from any number of plant groups- annuals, perennials, shrubs, climbers and grasses.
True annuals and those plants we tend to treat as annuals such as the tender bedding plants are often at their best in August especially if they have been watered, fed and dead-headed over the early summer. On our patio and within the beds and borders Pelargonium, Fuchsia, Cosmos, Nemesia, Verbena, Antirrhynum, Argyranthemum and Zinnia are all in full flower and with continued care will hopefully go on into the autumn. The true annuals such as the Sweet Peas in large pots and Sunflowers and Calendula in the beds are also providing welcome splashes of colour.
The lovely Argyranthemum from The Canaries and Madeira. This is just one plant!
These are obviously the result of some forward planning in terms of seed sowing and raising plants from plugs earlier in the year as well as some regular care and attention but the second group- the Herbaceous Perennials once planted will largely look after themselves apart from possibly needing some physical support, dead-heading and cutting down at some stage in the dormant season. There is also a large range of plants to choose from as some early summer plants will still be flowering well such as Penstemon and Phlox, others are autumn flowers which have just started to come into flower such as Aster and Rudbeckia and others still are the real late summer flowers which are at their best in August. In our garden Penstemon are still doing really well and by August the first flowering shoots have been dead-headed to make way for the next flush of blooms. August is also a good time to take softwood cuttings just in case we have a hard winter and because Penstemon with their woody bases don’t divide easily like many other perennials.
Penstemon ‘Sour Grapes’ Penstemon ‘Raven’
The Phlox which we grow in slightly shaded parts of the garden began to flower in late July but with dead-heading will continue to do so into and hopefully beyond August. If you have problems with powdery mildew on Phlox paniculata (Perennial Phlox) then try Phlox maculata (Meadow Phlox) which never seems to suffer from this unsightly problem.
Phlox paniculata Phlox maculata
We also have flowers on the Japanese Anemones (Anemone x hybrida and A. hupehensis) which began to appear in late July even though in most years they start at the end of August. Possibly this early flowering is the result of this year’s hot, dry spring but whatever the reason they are a welcome addition to the August garden as in the case of Anemone ‘September Charm’ which seems to be seriously confused! After a few years they form substantial clumps with their attractive 3-lobed leaves above which sturdy stems bear many open, saucer-shaped flowers in white or various shades of pink with a central boss of stamens. If you only have one Japanese Anemone make sure it is Anemone x hybrida ‘Honorine Jobert’ with her single, white flowers, pink tinged on the reverse with golden yellow stamens- she is a real beauty!
The rather lovely but slightly confused Anemone ‘September Charm’
Our real star of the August garden is yet to show any flowers as I write this at the end of July but the buds are there and by the end of August our two plants will be full of flower heads with pale yellow, outer ray-florets and darker yellow, inner disc-florets. This is the majestic and rather large Helianthus ‘Lemon Queen’. In April the first signs of life appear from the ground and by August the Queen is 4-5 feet tall and full of flower buds. Like most Queens she does require a bit of support in the form of, for us at least, a wigwam of canes and quite a few loops of garden twine. She is not for the small garden but at the back or middle of a large border she certainly earns her place. We have two plants now because after 2-3 years in the garden our first plant was divided into several pieces, some of which were passed on to members of the Old Railway Line “Great Oaks” gardening club and we hope they are now enjoying the Queen as much as we do. Division is a really good way of producing new plants for free and at the same time rejuvenating the old plant as vigorous perennials tend to get rather old and woody in the centre. By dividing the woody centre can be discarded and the younger, outer parts split up to form new plants. This can be carried out in the autumn when the soil is still warm but I prefer to do it in the spring just as the plant starts to show some growth. The whole plant is lifted with as little root damage as possible and then divided up using a knife, spade or two forks back to back depending on how old and woody the plant is. Any damaged roots can be trimmed back before the new sections each with roots and buds are replanted in enriched soil or potted up.
Another good plant in the August garden is the spiny, silvery- leaved, blue thistle-like flowered Eryngium (Sea Holly). Most come from dry, rocky parts of Europe, North Africa and Asia so require well-drained soils in the sun. Most plants with small, narrow, silvery or grey leaves which are designed to reduce water loss are ideally suited to fairly poor but well-drained soils in sunny positions and do not welcome cold, wet soils in the winter. Adding grit to the planting hole and adding very little, if any, fertiliser is always a good plan with such plants. This certainly applies to that other generally blue-purple flower of the late summer, even though strictly speaking it is a shrub, the wonderful Lavender (Lavandula), much loved by bees and great for fragrance both in the garden and in the house. In West Wales we grow our Lavenders in large, shallow ceramic bowls in very gritty compost so that they can survive our rather wet winters! One problem with Lavenders is that they can become rather untidy and woody with age but this can be avoided or at least delayed by careful pruning. There are two schools of thought on pruning Lavenders- one says that it needs to be done in the autumn and the other is certain that they are better pruned in the spring! In order to cover myself I do a bit of both! In autumn once the seeds have fallen or been eaten by Goldfinches, which in itself is a sight to behold, I cut the old flower spikes back to just above the point where this year’s green/grey growth began. Cutting further back into old wood is not a good idea which is why old, woody plants are very difficult to rejuvenate and are best replaced with new plants. In the spring I just give them a tidy up by removing any winter-damaged growth again avoiding cutting back into the older wood.
I could go on at length about good, late summer herbaceous perennials but I must stop somewhere! Suffice it to say that there are lots to choose from as I have listed below. Have a look around the garden centre itself or do a virtual tour on the website to choose your own favourites. If you do your August garden will not disappoint in the future. Earlier this week we actually paid our first visit to the Old Railway Line since lockdown began and I have to say it was a very pleasant experience. The management and staff have clearly worked very hard, not only to keep the centre looking as good as it always has but also to make everyone’s visit as safe and comfortable as possible. We shall certainly be going back soon and I can’t say that for many of the shops which we have ventured into in the last few weeks!
Some other perennials to consider:- Agapanthus, Alcea (Hollyhock), Aconitum (Monkshood-poisonous so be careful!), Campanula eg. lactiflora, Canna, Cephalaria gigantea, Cosmos atrosanguineus (chocolate scented!), Crocosmia, Dahlia, Echinacea, Eupatorium purpureum (Joe Pye Weed), Gaura, Hemerocallis (Day Lily), Knautia macedonica, Knifophia (Red Hot Poker), Liatris, Lilium, Lithrum salicaria (Purple Loosestrife), Lychis coronaria (Rose Campion- biennial), Sedum eg. ‘Spectabile’ and ‘Autumn Joy’, Stokesia, Verbena bonariensis, Veronica eg. prostrata and spicata.
If these are not enough for you then there are also some shrubs which are looking good in August. There might be fewer to choose from but they will still produce masses of colour and interest in August and beyond. I have already mentioned Lavender and following it alphabetically is the showy Lavatera (Mallow). These provide lots of colour in the late summer with their 5-petalled, saucer or funnel- shaped flowers in colours ranging from white through all shades of pink to magenta and lilac, often with eye-catching veining leading into the centre of the flower. They can be rather short-lived but in their prime are worthy of their place in the August garden. I have waxed lyrical in July about the Buddleja and Hydrangea both of which are still going strong for us in August.
A Lacecap form of Hydrangea macrophylla Hydrangea paniculata ‘Angel’s Blush’
However, there are other shrubs which are only just starting to flower at this time such as the blue flowered Caryopteris and Perovskia (Russian Sage). During the winter both of these can suffer from die-back of the younger shoots so in spring they need to be cut back to live wood lower down. The flowers then appear on the current year’s growth at the end of the summer which makes them particularly attractive to both gardeners and insects. This is also the time when the Hardy Fuchsias come into their own and if you like Fuchsias then have a look at Phygelius (Cape Fuchsia or Cape Figwort) from South Africa. They are a really showy plant with hanging, tubular, Fuchsia-like flowers in strong, hot colours of reds, oranges and yellows. They like a hot, sunny site and can get damaged in our winters but after cutting back to live wood in the spring usually survive to produce another summer show.
Other good late summer shrubs include:- Abelia, Ceanothus ‘Autumnal Blue’, Calluna and Erica (Summer flowering Heathers), Hebe eg. ‘Great Orme’ and of course the repeat flowering Roses.
There are also some very useful late summer flowering climbers apart from the repeat flowering Climbing Roses. These include:- Campsis (Trumpet Creeper or Vine), Clematis eg. ‘Niobe’, ‘Jackmanii’ and any of the Viticella Group, Ipomoea (Morning Glory), Lonicera eg. periclymenum ‘Serotina’ (Late Dutch Honeysuckle) and Passiflora (Passion Flower).
Finally for the August garden I am going to put in a good word, or two!, for a group of plants which I think are still underrated by many gardeners and that is the grasses. They may not be as colourful as the other groups but their foliage and seed heads can add a great deal to the late summer border with their graceful movements and strong vertical lines.
Grasses fall into two main groups- ‘Cool Season’ and ‘Warm Season’. The Cool Season as their name suggests grow and produce their seed heads early in the growing season but as their foliage and seed heads remain attractive for many months they still offer something to the late summer garden. These include:- Carex, Festuca, Calamagrostis, Hakonechloa, Heliotrichon (Blue Oat) and most of the Stipas including Stipa gigantea (Giant Oat), S. tenuissima (Feather Grass) and S. arundinacea (Pheasant’s Tail Grass).
The Cool Season grass Hakonechloa macra ‘Aureola’
However, in the late summer it is the Warm Season grasses which steal the show as they flower at this later time. They generally prefer a sunny position but can tolerate less fertile soils than many of the other plants I have already mentioned. They are best seen against a darker background and when the sun is beyond them or to the side. These grasses include:- Cortaderia (Pampas Grass) eg. ‘Pumila’, Miscanthus eg. sinensis ‘Zebrinus’ or ‘Morning Light’, Panicum eg. ‘Strictum’, Pennisetum (Fountain Grass) eg. alopecuroides ‘Hameln’ or ‘Little Bunny’.
A Warm Season Miscanthus grass with the dark-leaved Sambucus ‘Black Lace ‘ in the background
I hope you can see from all the above that there are lots of beautiful plants to light up the August garden and that there is every reason to enjoy the late summer garden as much as we enjoy other times in the year. As for August jobs, they are listed in the Blog archive section for when you have a moment! We will be concentrating on getting as much as possible from the vegetable pots, beds and from the greenhouse. This means watering and feeding as well as weeding and watching out for pests and diseases. In the ornamental garden there will still be plenty of dead-heading to do and the conifer hedges will need their final cut of the year towards the end of the month as there will not be much new growth after that.
Whatever you are doing in the August garden enjoy yourselves and keep safe and well.
The next blog on the second part of the Basics of Garden Design will come out around the middle of the month and then we are into September. Where does the time go when you are enjoying yourself?