Take advantage of the last wave of summer
Trim, tidy and renew the garden this month and it will look good for the rest of summer, writes Alice Spenser-higgs
SUMMER gardening comes in waves. There is the early start in September, full throttle in October (depending on the weather) and the final push in January when everything is put in place for the last months of summer.
The garden programme for January mostly requires trimming back the rampant growth after festive season neglect, filling in gaps and replacing plants that look tired.
Kirchhoff’s Marlaen Straathof says that with four to five flowering months ahead of us it doesn’t make sense to nurse plants that are not looking good. Rather put in a new batch of plants or opt for a colour bag if you just need to fill a gap or two.
Straathof suggests a number of tough summer survivors for sun that will keep on flowering until the first frost. Marigolds, such as the Durango (French marigold) or Taishan (African marigold) are both hardy garden plants that never stop flowering. Durango (20cm to 25cm high) has anemone type flowers on strong stems, while Taishan (30cm to 35cm) has large double flowers that look like pom-poms.
Zinnias such as the new generation Zahara are more compact, disease resistant and showy. The range has single or double flowers, grows 30cm to 40cm high and is available in single colours or mixes such as Bonfire (scarlet, fire and yellow) or Lemonade mix (coral rose, yellow and starlight rose).
There are various salvias, including Salvia microphylla Hot Lips, one of the most striking varieties with white blooms and full red lips. It has a height and spread of 40cm to 60cm and forms a mound of broad, soft aromatic leaves.
Angelonia is not yet as well known as other garden flowers. Its common name is the summer snapdragon and it can be used as an alternative for salvia because it likes the same growing conditions and is drought tolerant. Regular watering is required until plants are established.
There are two different types of Angelonia. Angelonia angustifolia Serena is a dwarf, well-branched plant, 30cm high and wide, that stands up to our summer thunderstorms and extreme heat with ease. It doesn’t need pinching to maintain its low-mounding form. Individual plants should be spaced 15cm to 20cm apart.
There are five soft colours available in this series and they all blend well together: Serena Lavender, Serena Lavender Pink, Serena White and Serena Blue, which is the newest addition to the range.
Angelonia angustifolia Angelmist is a vegetative variety that is available in a large range of colours as well as in three different forms as a low, spreading plant, a compact 25cm to 35cm high plant and a taller, vigorous 35cm to 60cm high plant.
In US trials they have shown an exceptional tolerance for heat, humidity and drought.
The colour range includes lavender and a lavender bicolour, plum, purple and purple stripe, white, deep rose, pink and blue.
In areas with shade New Guinea Impatiens Divine is still the best choice. At the beginning of summer when the nights were still cool it grew slowly, but it has taken off now that night temperatures are higher.
If you need a plant for those difficult areas that get sun and shade almost in equal measure, try Begonia Dragon Wings.
A single plant quickly fills a metre-square area with an abundance of red or pink flowers, and the wing-shaped leaves always look glossy and healthy.
Baby Wings is a mini version of the Dragon wings, with a more upright, less spreading growth habit and smaller leaves with pink or white flowers.
Fertilise the lawn to replace nutrients leeched out by the December rain. Use a 5:1:5 fertiliser or Vigorosa (5:1:5) and water in well afterwards. Vigorosa can also be used to feed the flowers and shrubs.
The last task is to get rid of all the weeds before they flower. The best time to weed is after the rain when the soil is soft.