Long-blooming summer plants

Sunday, 24 November 2013

Perennial Cleome in the garden of Kathryn Hipkin in Brisbane

I was recently asked for some suggestions of plants that flower for a long time in the garden. One answer to this question (especially for those who live in warm temperate or subtropical climates) is to choose summer-flowering shrubs, perennials and annuals, because they have a much longer period of bloom than spring flowers in many cases. I actually steered my garden to be at its best in summer and autumn when I realised how relatively short was the time spring bloomers lasted compared to those plants that flower when the weather heats up. Nowadays, I tend to visit other people's gardens in spring to admire those achingly gorgeous blooms rather than have them in my own plot.

Salvia microphylla Angel Wings

The genus Salvia is the first to come to my mind when recommending long-flowering plants, as they really do have an incredibly extended blooming time. Many of them flower from autumn all through winter; the summer bloomers begin around October and keep going till May. There are just so many species and cultivars around these days to choose from, but my own personal favourites include Salvia guaranitica Large Form, 'Joan', 'Wendy's Wish', 'Phyllis' Fancy', 'Van Houttei' - and many of the small-sized S. microphylla cultivars. At a garden stall at an open garden in Brisbane last weekend, I was interested to see how many cultivars of these are available in Queensland that I had never heard of. I purchased a very pretty one called 'Angel Wings', with pastel pink flowers held in dark calyces (pictured above). I look forward to trialling it in my garden.

Pentas are also fabulous long-bloomers, beginning in late spring and continuing on until early winter. They grow best in sun but some of the varieties (especially a red one that I grow) do well in part-shade. The family Acanthaceae has summer-flowering members that are floriferous for months - including Justicia carnea, Justicia brandegeeana, Justicia betonica, Ruellia elegans, Brillantaisia subulugarica and Thunbergia grandiflora. In my friend's Brisbane garden, I saw a bright pink-flowered cultivar of Ruellia elegans called 'Firebird', which was very attractive growing nearby the similarly coloured veins in the leaves of Iresine herbstii 'Brilliantissima'.

Hydrangea shrubs are in flower now in Sydney and will continue for many months to come - giving them great value in shady parts of the garden. There are so many different ones available these days - lacecaps, double-flowered varieties, compact forms and so on. They need reasonable moisture but once established are pretty tough - especially the old-fashioned, thick-stemmed types. Almost all of mine have been grown from cuttings from other people's gardens. Another great shrub for shady spots is the cane-stemmed Begonia. In bloom for easily nine months of the year from November onwards, they bring stunning pendulous flower heads in colours of pinks, white, red and orange and ask nothing more than to be pruned back in early spring to give them a new lease of life. The shrub-like Begonia cultivars are also excellent long-flowering plants for shade.

Dahlia plants are also great value for a lengthy display period. They grow easily in Sydney gardens and don't have to be dug up except when you want to divide them. By pinching off the spent heads every so often, the flowering time can be extended from November to around May. There are many pretty colours and forms to be had and they revel in summer's heat. I have a fondness for the dark-leaved types, such as 'Moonfire', but they are all good plants. They associate well with Salvia plants.

I have a fondness for long-flowering summer annuals in my garden, especially those that come up every year through self-seeding. I have grown Cleome ever since the first summer in my present garden. Recently, I was pleased to receive a perennial form of Cleome (pictured at the start of the blog). There are pink and white forms of this, and they are shorter and more compact than the annual one, and flower almost all year, apparently. Amaranthus caudatus, with its long burgundy tassels is another of my favourite summer annuals. In bloom now, it will not give up until early winter. Hundreds of seedlings come up in my garden each spring and I pull out all but a couple: these quickly develop the stature of small shrubs. During my sojourn in Brisbane, I was also reminded of other worthwhile summer annuals, such as Catharanthus roseus for sun and the brightly hued New Guinea Impatiens (which don't seem susceptible to the fungus that wiped out other species of Impatiens in recent years) for shade, and I vowed to add these to my garden this season.