Chris Dalzell
It is crazy to think that we are more than halfway through January and now into the hottest time of the year.
I have never been a fan of hot, humid weather but if you live in the subtropics you will experience at least two months of intense heat from late January through March. I lived in Singapore for more than two years where you experience high humidity 24/7 which is never easy. When you are a gardener, you live outside most of the day.
So how do we plan work in our gardens around these humid days? Here are a few tips:
Work early in the morning and late in the afternoon. The early sunrise gives us time to do any watering required before heading for work. If you are not an early riser, do it when you get home from work before it gets dark.
Make sure most of your planting is done in the cooler times or on one of the few cooler days which occasionally happen. Any major landscaping must be completed before it gets too hot. If you have a shade house or nursery, water in the early morning because watering in the middle of the day causes high humidity.
Check your plants for fungal and pest problems as both thrive in high humid conditions.
If shrubs have grown too big, prune them back to at least half their size. This prevents pests and diseases attacking your shrubs, which if left alone will spread to other plants.
If you have lots of trees in your garden this will help keep your place a little cooler as trees absorb the heat.
Make sure you drink lots of water and wear sunblock.
Summer always brings lots of grassland flowers, plus we have a lot of trees and shrubs that flower in summer which you can see in the Highway area. Only this week I noticed for the first time that the tibouchina trees from South America are in bud and within the next few weeks will be in full flower. I know they are exotic, but they create so much colour and beauty that gives a lot of pleasure to so many people.
Last weekend I was at Babanango Game Reserve up in Northern Natal showing a group of enthusiastic plant nuts the flowering grasslands, trees and shrubs.
A tree genus that flowers particularly well in summer is Pavetta, which has more than 400 species in the old-world tropics and 21 species in South Africa of which most grow in KwaZulu-Natal. The two species that grow particularly well in many gardens around Durban are pavetta lanceolata, the weeping bride’s bush and pavetta edentula, the gland-leaf bride’s bush.
Easily grown from seed, these trees and shrubs flower from early December through February. They don’t grow into large trees and make a wonderful display in gardens during the hot, humid summer months.
To complement the white flower of the bride’s bush is another very fragrant tree called gardenia thunbergia, white forest gardenia. Its flowers open at night, attracting the hawk moth to feed off its sweet nectar and pollinate its flowers. Once pollinated it produces a large seed pod that can remain on the tree for many years.
If the trees get too large for your garden you can prune it by at least 50% after its flowering. This gives the tree sufficient time to recover and produce new growth for next summer.
One of my favourite summer-flowering shrubs is karomia speciosa, mauve or summer Chinese-hats. Its mauve flowers produce a sharp contrast to the green landscape which attracts many butterflies that feed on its sweet nectar. Once it has finished flowering in late January you can prune it to half its size, ready for new growth next season.
Even if you add just these few plants to your garden, it will make such a difference to your summer season of flowers.
Things to do this month
Prune shrubs before the onset of autumn. This will allow the shrubs time to recover and produce sufficient growth for the following season. Prune shrubs to at least a third of the size of the plant. Use a sharp pair of secateurs which will prevent any damage to the delicate branches.
Cut lawns at least twice weekly. This will keep your lawns healthy, produce a healthy root system, prevent damage to the grass if it gets too long and encourage new growth the spread evenly over the entire surface. Good time to top-dress with a well calibrated and even mix of river sand, compost, and well decomposed bark. Do not put a thick layer of top-dressing as this can damage your lawns.
Fertilise all your indoor and outdoor pots with a slow-release fertiliser such as osmocote. If plants are root bound in the pot, remove the entire plant from the pot, clean off all the old growing medium plus dead or damaged roots and repot into a larger pot with new growing medium. Water well after potting so that the water runs out of the bottom of the pot. Make sure you do this all outdoors. Remove any dead or damaged leaves as this can harbour diseases and insects. Check for insects on the leaves and roots.
Collect seeds of many of the early summer flowering bulbs. Crinum macowanii and Crinum bulbispermum are two extremely easy bulbs to collect seed from and propagate. At the end of the flower spike, you will see a large head of seeds which will burst from there seed coating. Take each seed and place on top of a tray with potting medium or river sand. Cover the seed partly. Within a few days these seeds will all germinate. Once they get too a decent size with leaves and roots, remove and plant in the garden.
Continue to plant your veggie garden. Buy seedlings in trays of 4-6 and ensure you give the soil lots of well decomposed compost to provide nutrients to the soil and allow the new roots to grow quickly. Monkeys are a problem but it’s worth it.
Happy Gardening
- This article is sponsored by Chris Dalzell Landscapes, specializing in landscaping, consultation, plant broking and Botanical tours. If you have any questions, email cgmdalzell@gmail.com or visit www.chrisdalzellinternational.com
The Independent on Saturday