The July Garden 2022
Something I always think about when we get to July is where on earth did the first half of the year go? It doesn’t seem that long ago that I was venturing out into a cold and often wet January garden and anticipating the growing season to come. By July the garden is a very different place with all of its high summer colour, scents and abundance of growth. All the hard work of the earlier months has paid off and resulted in full and luxuriant beds and borders as well as lots of tasty and healthy edibles in the vegetable beds, pots and greenhouse- the very welcome rain towards the end of June helping a great deal.
As always Teresa and I have enjoyed our June garden where the stars have included our wonderful, and free!, Foxgloves (Digitalis purpurea), Astrantia, Red Campion, Cornflower (Centaurea montana), hardy Geraniums, Common Sage (Salvia officinalis), Valerian and in the shrubs Deutzia, Philadelphus and Roses and are now looking forward to our ‘July’ plants including Betony, Cosmos, Hemerocallis (Day Lily), Hosta, Lychnis coronaria, Buddleja, Hydrangea, Roses, Sambucus ‘Black Lace’ and various grasses. More details and photographs on all of these plants can be found in the blog archives for July 2021 and July 2020 which for some reason is listed under June 2020. In addition to these we are also expecting great things from the three plants which I will concentrate on for the rest of the blog- Dahlia, Penstemon and Salvia, three truly wonderful summer plants.
Dahlias– named after the Swedish botanist Anders Dahl
This is an inspirational flower- whole gardens are dedicated to it, societies form in its worship, shows are held to honour it and many plant breeders have given their lifetimes in the pursuit of its perfection. It is a genus of about 30 species and over 20,000 cultivars of bushy, usually tuberous-rooted perennials originally from mountainous areas of Mexico and other parts of Central America. They are grown for their striking flower heads in colours from white, red, orange, yellow, pink and purple which are on the plants from July until the first frosts of autumn when many other flowering plants are past their best. They are generally divided into two groups- tall and dwarf- with the taller ones combining well in mixed borders with other late flowering plants such as Salvia and grasses and the dwarf cultivars ideal for colour in summer containers or the fronts of borders. They are therefore excellent for garden display, cutting for the house and for exhibition purposes. They are classified according to the form of their flower heads with perhaps the best known ones being single, waterlily, anemone, pompom, ball, cactus, orchid and peony.
Dahlias are best grown in full sun in a fertile, humus-rich, well-drained soil and benefit from a high nitrogen feed in early summer followed by a high potash feed for the rest of the summer and autumn. The taller dahlias do require some form of support and all dahlias should be dead headed as the flowers fade and when the bud becomes pointed rather than rounded. Traditionally after the first frosts have blackened the top growth the tubers are lifted, the soil brushed off and are then placed in a frost-free place to dry naturally. They can then be dusted with fungicide if required and packed in boxes of peat-free compost, bark-chippings or dry sand to be stored frost-free over winter. Tubers are then replanted in early spring (March) and grown on in a greenhouse before being planted out after the danger of frost has passed. In more recent times, however, many gardeners now leave dahlias in the ground over winter protected by a thick layer of mulch. This seems to work particularly well in milder areas, in well-drained soils and with some of the more modern cultivars particularly those with darker leaves.
Low growing, bedding dahlias can be grown from seed sown in warmth in early spring and planted out in late May/early June. The larger dahlias can be propagated by taking basal shoot cuttings from the tubers started into growth in the spring or by dividing the growing tubers into smaller sections each with a shoot.
One of my favourites and still, I think, the best ‘Bishop’ is Dahlia ‘Bishop of Llandaff’ which is grown almost as much for its reddish-black foliage as for its bright red, semi-double flowers. This is a plant which I over wintered in the ground for a few years in a well-drained Herefordshire soil. The ‘Bishop of Llandaff’ is a good example of the increasingly popular dark-leaved dahlias whose vibrant flowers really stand out boldly against the dark foliage. They certainly add depth, contrast and interest to mixed borders and exotic plantings. Other good dark-leaved plants include D. ‘Waltzing Matilda’ (orange/coral pink), D. ‘Fascination’ (pink), D. ‘Happy Single Juliet’ (lilac-pink with dark yellow centres) and D. ‘Hadrian’s Sunlight’ (yellow with a darker yellow-orange centre). In terms of the dwarf dahlias it is hard to beat D. ‘Yellowhammer’ which is a more tender perennial grown as an annual bedding plant for patio pots or the fronts of borders. It has attractive bronze-green leaves and clear yellow, single flowers.
Dahlias used to really good effect in the ‘hot’ border at the entrance to Aberglasney Gardens
Penstemons– named because all their flowers have five (pent) stamens.
Penstemon ‘Raven’
This all-American beauty has become one of the world’s favourite perennials gracing many borders and cottage gardens which is not surprising given their long flowering period, easy going habit, vividly coloured tubular flowers and their popularity with bees. It is a genus of around 250 species of deciduous, semi-evergreen or evergreen perennials and sub-shrubs from North and South America now joined by many modern cultivars and naturally occurring hybrids. Penstemons are members of the same family as Foxgloves (Digitalis) and Snapdragons (Antirrhinum). The flowers themselves are tubular and two-lipped with the upper lip usually two-lobed and the lower lip three-lobed. They flower from late June to mid or even late-autumn in a range of colours including white, yellow, all shades of pink, red, blue and purple. Many flowers have different colours or shades of colour on the insides and outsides of the flower tubes and in addition the insides often have attractive markings. For example Penstemon ‘Alice Hindley’ has large, tubular-bell-shaped, pale lilac-blue flowers white inside and tinged mauve-pink outside, P. ‘Apple Blossom’ has smaller, tubular-bell-shaped, pale pink flowers with white throats and P. ‘Sour Grapes’ has tubular-bell-shaped, rich purple flower each with a white throat and purple markings. An old and reliably hardy favourite with gardeners is P. ‘Garnet’ (sometimes labelled as P. ‘Andenken an Friedrich Hahn) a vigorous, bushy, narrow-leaved perennial bearing small tubular-bell-shaped, deep wine-red flowers which make it perfectly suited to any ‘hot’ colour scheme planting. Other excellent varieties are P. ‘Raven’ (dark maroon) and P. ‘Osprey’ (pink and white).
Penstemon leaves are generally narrow with any larger leaves being more elliptical or ovoid. Larger species and cultivars are generally grown in beds and borders and smaller ones in the rock garden or the front of a border. They do best in fertile, well-drained soil (root-rot through overwatering or poor drainage in the winter is the bane of all penstemons) in full sun or partial shade and unless seed is required benefit from regular dead heading to extend the flowering period and to some extent to control their height and spread. They are easily propagated from soft wood cuttings in early-summer or semi-ripe cuttings in mid-summer and this is always a good idea if gardeners have any worries about the main plant surviving the winter. Having said that many varieties are semi-evergreen in British winters particularly in milder areas and growth should be left on until April partly to protect the newer growth lower down and partly as the experts say to ‘give the roots something to do during the winter’. In April they should be cut back quite hard to good, strong growth lower down.
Salvia- Sage– from the Latin ‘salves’ meaning ‘I heal’ or ‘I save’
Salvia is a genus of about 900 species of annuals, biennials, herbaceous and evergreen perennials and shrubs. These are found world-wide in temperate and tropical regions in sunny sites in meadows, rocky slopes and light woodland. They are frequently aromatic and often hairy both of which are indicative of plants which prefer warm and dry conditions. They have square stems bearing opposite pairs of leaves. They come in a large range of colours and the flowers themselves are two-lipped, the upper lips erect and hooded, the lower ones two-toothed and more spreading and form interrupted terminal spikes or racemes. These nectar-rich flowers are a magnet for bees, butterflies and other pollinating insects. Different parts of the plants as the Latin name suggests have either medicinal or culinary uses. Some Salvias are very effectively used in sunny borders, in light woodland or wildflower meadows. Others can provide brilliant colour for bedding schemes, infilling or containers. They can also look good in a tropical or exotic planting scheme alongside Dahlias, bananas and Cannas. They prefer moderately fertile, humus-rich, well-drained soil in full sun to light, dappled shade. Some can be grown from seed, others are best divided in spring and yet others can be propagated from soft wood cuttings in spring/early summer or from semi-ripe cuttings in mid/late summer.
Salvias can be divided into four main groups-
Annual Salvias such as S. splendens are grown as vibrant summer bedding before being discarded at the end of the summer.
Herbaceous perennials Salvias such as S. nemerosa and S. x sylvestris are hardy and will come back reliably year after year
Tender perennial Salvias such as S. greggii can come back year after year but are not completely hardy and may need some winter protection
Shrubby Salvias such as S. x jamensis ‘Hot Lips’ and S. microphylla are sub-shrubs with woody stems. Most are hardy and evergreen in mild winters but they may also need some winter protection.
As they are not all fully hardy as the above shows there are several things the gardener can do to enjoy Salvias from year to year-
Take cuttings in late-summer (Aug/Sept)
In milder areas add a mulch of bark, compost or well-rotted manure in the autumn
In colder and also wetter areas lift plants as you would with Dahlias and over winter indoors
Don’t cut back growth in autumn, wait until late spring cutting the plants back to quite low down just above the fresh shoots that appear at the base.
Perhaps one of the easiest Salvias to grow and also the best known is Salvia officinalis, the Common Sage, with its grey-green, woolly, aromatic leaves and lilac-blue flowers in early/mid-summer. It is of course a popular culinary herb and now has several cultivars such as S. officinalis ‘Aurea’, ‘Kew Gold’, ‘Purpurascens’ and ‘Tricolour’ with grey-green leaves with cream, pink and purple patches. Also widely grown is Salvia x sylvestris with lance-shaped, wrinkled and hairy mid-green leaves and racemes of pinkish-violet flowers. Many of its cultivars such as S. x sylvestris ‘Blue Mound’, ‘Blue Queen’ and ‘Mainacht’ (May Night) have rich blue-violet or indigo-blue flower spikes. Another good ‘blue’ and reliably hardy is Salvia nemerosa ‘Caradonna’ with its upright racemes of violet-purple flowers above narrow, rough, grey-green leaves. For a more naturalistic look Salvia sclarea (Clary) is a good plant. It is a biennial or short lived perennial but seeds around generously. It grows up to 3 feet (1m) and has strongly scented, wrinkled, oblong leaves and long racemes of pale pink flowers with conspicuous mauve-pink bracts in late spring and summer. Finally S. splendens has long been used as an annual border salvia with is blazing, red-toned flowers.
I hope the above has stimulated your interest in these three really good ‘summer’ garden plants and that you might be able to fit one or more into any gaps you can find in your beds and borders as we move into July. Choosing the right plant for the right spot and knowing how to look after it properly gives the plant every chance to perform at its very best which is all we can ever ask of our plants. I wish you every success.
As far as jobs for July go a full list can be found in the blog archives for July 2019 and details of what Teresa and I will be concentrating on in our garden can be found in the July 2021 blog. Essentially these consist of watering when and where necessary, dead heading, making the best of the vegetable bed and caring for tomatoes in the greenhouse.
The Great Oaks talk for July will be on Saturday 9th at 9-30am in the Tearoom when I will be able to give Dahlias, Penstemons and Salvias centre stage by featuring some of the lovely plants which the Old Railway Line has to offer in addition to attempting to answer any gardening questions which come up on the day. I hope to see you there.
In the August blog I will be highlighting some of my favourite plants which grace the month and will show them off in the August talk on Saturday the 6th.
Until then keep well and enjoy your July garden.
Keith