Is summer over yet? It certainly should be by now, and I keep waiting for it to be so I can write this blog! It was certainly one of the cruellest Sydney summers in my memory, with the extreme lack of rain and day after day of intense heat. It certainly wasn't like the summers I seem to remember 10 or even five years ago.
However, I have certainly learned a lot from it. The obvious thing to me is that our summer weather patterns are certainly seem to be changing. Even with my rustic, handwritten rain gauge charts going back several decades, I can see that we no longer get the summer rain that we used to experience. I don't keep temperature records but it appears that the number of days over 35 degrees C each summer in Sydney has increased dramatically over the past decade. Gardeners, on the whole, are very attuned to weather, perhaps more than many of the population.
As an individual gardener, what can one do? I've decided that I can no longer keep those thirsty plants that complain and wilt dramatically on the increasing number of hot days. Out they must go! However, in some cases, the problem can be resolved by moving the plants to a shadier and/or moister location in the garden, if they are special favourites. I'm increasingly realising that shade is a precious commodity in our hotter summers, and plants that fry in full sun are much more likely to survive if they can have the protective canopy of a tree or tall shrub, where temperatures can be significantly cooler than positions in full sun. We probably need to plant more shade-giving specimens in our gardens! Examples of plants I plan to move (when the weather does eventually cool down!) include Salvia dorisiana (pictured above) and some other large-leaved Salvia; some of my fancier cane and shrub Begonia specimens, which can tolerate some sun but really suffered on the very torrid hot days we had last summer; and ditto my Fuchsia hybrids. I have realised that we simply may not be able to grow plants that will be out of their comfort zone if these hot, dry summers become the norm. I lost two mature shrubs this summer and some other smaller plants. We need to look at plants that do seem to be able to cope, and plant more of them. Not surprisingly, they are mainly plants from semi-tropical parts of the world that enjoy heat and humidity!
I also found out, the hard way, not to plant new specimens in spring any more. This used to be a good time to plant, but these days, the heat starts arriving much earlier, before plants have time to really establish themselves. Autumn now seems the best time to plant -- yet even so, I am still waiting for an opportune time, because of the ongoing heatwave! This April has already broken records for unseasonably hot days. Perhaps May will be cool enough? We ideally want a time when the soil is still warm to allow roots to establish but not too hot. Traditional gardening practices look set to have to change if these weather patterns persist. As another example, I won't be taking cuttings in spring in future, because it is too hard to keep the rooted plants in pots alive over summer. I also plan to cut down the number of potted plants I have in general, because of the ongoing need to water them in heatwave conditions.
A more positive thing I discovered last summer was about the phenomenal growth that goes on throughout the season, and how this can be harnessed to our advantage. I had a garden group visitation in early March, and I decided to lightly cut back plants that were looking a bit ratty back six weeks before that, at the start of February, including all my summer-flowering Salvia cultivars, seaside daisy (Erigeron karvinskianus), Gaura, perennial Ageratum, Cuphea shrubs, perennial Cleome, Tulbaghia violaceae (cut completely to the ground) and foliage plants such as Iresine, Alternanthera and Artemisia. I felt rather nervous about doing this but they all grew back well and were flowering again by the time of the visitation.
I also deadheaded spent flowers regularly - particularly Dahlia cultivars, Canna, Pentas shrubs, summer-blooming Spiraea japonica and perennial Phlox. This small task really pays off in terms of prolonging the floral display. I also continued to deadhead the plants that I had cut back at the start of February once these began to flower again. I didn't fertilise much this past summer because I felt the weather was too hot for it, and I was hopeful that my new way of mulching, using half-decomposed shreddings from the mulcher, mixed with cow manure, was helping to feed the plants as it broke down.
I did water though, as I mentioned in one of my blogs, and I do feel guilty about that. My dripper hose system that normally works well just didn't seem to be coping with the extreme heat and dryness and so I ended up putting the wasteful sprinkler on. I am toying with the idea of reinstalling a mini-jet system -- we once had one and I was very happy with it but at one stage these were banned, so we took the whole thing out. I'd love to know what other readers feel works best for them for irrigation in our 'new normal' summers ... and what you learned last summer.
22 Nov 20
These plants love heat!
15 Nov 20
What a great year for hydrangeas!
08 Nov 20
Brighten up your garden with some of these!
01 Nov 20
The concept of colour echoes can be used to create harmony and cohesion in planting schemes.
Creative pest control
25 Oct 20
There are lots of ways to outwit garden pests!