After all the work required in January, it is nice to realise that February is more a time of waiting and patience. Some pruning can be done now, but wait for warmer weather before cutting back any frost-damaged branches.
Fertilise deciduous fruit trees and avocados in coastal zones but wait for March before feeding other plants or putting in summer vegetables and flowers. You can crack on with soil preparation with some digging, weeding and manure.
A mature tree will need at least 1 kilo of nitrogen every year as well as other nutrients, namely phosphorus, potassium and zinc, from time to time. It is easiest to use a proprietary fertiliser with these elements – similar incidentally to that used for citrus – usually in a 25-18-10 proportion or 16-8-4. Divide the total for the year into four equal applications for March through to June. If you use slow-release feed (17-6-10), apply in two doses, with the first in March and the second in June.
Feed younger trees lightly as they don’t need so much nitrogen and can be harmed by too much fertiliser.
Otherwise, avocados need rich soil, good drainage, and a thick mulch covering the roots. Don’t rake up fallen leaves, but leave them in place. Don’t plant anything beneath the tree as that runs the risk of root damage which will affect the crop. Don’t allow water to sit on top of the roots as it may rot them.
Begin to fertilise in March.
Pests, such as aphids, mealybugs, and whitefly, become more active at this time of year, so monitor carefully. Rust mites, scales and ants are also potential damage-makers. Many problems can be avoided by keeping the trees clean from dust – spray them with soapy water such as 1 or 2 tablespoons of washing-up liquid per gallon of water.
Before spraying, remove branches that touch the ground to bar ants which love to feed on most pests which plague citrus trees. While it is beneficial for citrus branches to hang low, thus protecting the trunk from sunburn, any branches touching the ground should be shortened so that ants can’t jump onboard.
If pests remain a problem, you may have to resort to chemical sprays. Consult your local agricultural shop. Spraying when the trees are in bloom with some products may result in no fruit being produced and also in the decimation of the local bee population which serves to pollinate the trees.
Deciduous fruit trees
These may be fed when the weather warms up, in February or March, and the flower buds begin to swell. Give no more than ½ kilo of nitrogen per year to each mature tree in well drained soil, and less to any in clay soil. Feed younger trees more lightly. You can use the same formula as you used for citrus and avocado. Water deeply after feeding.
Start planting gladioli this month by putting in a few every other week until the end of March. This should provide you with blooms from June through the summer. They like full sun, light soil with bone meal added, good drainage and plenty of water. Plant small corms 7.5 to 10 cm deep and larger ones 10 cm to 15 cm deep. They do well also in containers, but need to be shaded from burning sun.
Water spring bulbs if the rains do not. Ranunculi should be under netting to protect from birds, but the netting can be removed when the plants are 7.5 cm high.
Give rose plants 2.5 cm of water from mid-February onward, unless the rains are sufficient. Wait to feed until the leaves unfurl and loose their reddish hue. Remember the date and repeat in a month, applying before watering.
If you choose to use chemicals to control disease, start spraying this month and do so early in the morning or in the evening when there is little wind. Chemicals can control mildew and rust but it is most effective to spray before the problem is discovered. Spraying against pests need not begin until next month. If you spot any aphids, try simply spraying them off with the hose or introduce some ladybirds.
Blooms come only on new wood. The plants need to be cut back annually to encourage growth and this is best done in February when some green growth has begun. Cut back to the old wood – that which is darker in colour and of a rougher texture. If in containers, remove about 1/4th of the topsoil, including roots, and replace with fresh acid soil mix. Begin to feed after pruning and then continue to feed regularly. As they grow, pinch them to make them bushy – when a sprout has made three pairs of leaves, clip off the top pair. When it has bulked out, stop pinching and let it bloom. Keep fuchsias in semi-shade and don’t allow the roots to dry out.
Annuals and Perennials
If you planted any cool-season flowers in October, they could have bloomed before Christmas and be in full bloom now; if you got them in late, they should start blooming this month. Continue to feed and deadhead the plants.
You can fill bare patches or containers with small transplants of some cool-season flowers, such as pansies, violas, calendulas and primroses, but they won’t last that long as they don’t flourish in warm or hot weather.
It is too early still to plant warm-season plants such as lobelia or marigolds, but you could start to plant petunias which won’t bloom yet but will use the time to create strong roots. Protect from frost and snails and fertilise.
By the middle of February you can cut back perennials that are woody and overgrown. Trim right back to the fresh new growth (basal growth) springing up at the base. But it is too late to cut back any which bloom mainly in spring, including lavender which should be tackled by pinching back the rangy tips to keep it compact and bushy.
Check your local nurseries to see what perennials and biennials they have newly in stock in February, but use your judgement as to any danger of frost occurring or the soil still being too cold or wet.
Late February is a good time to divide those perennials which die down to their roots in winter. Wait until they begin to grow again and show some signs of life before you divide.
Rains will have washed most nutrients to lower levels of the soil, so it is good to begin fertilising all perennials now.
Seeds for flowers and vegetables
It is still far too early to plant warm-season annuals and vegetables, but you can start some seeds now. Use flats or peat pots filled with sterilised potting soil and use bottom heat of 21º centigrade to germinate the seeds and plenty of light. Give the young plants a gentle transition into the garden by placing them first in the shade for a week, then one week in the sun – but bring them back in at dusk for the night time. By the third week you can leave them out overnight to harden them off.
Warm-season grass, especially those which have runners such as Bermuda, form thatch – a layer of partially decomposed grass blades, stems and roots which accumulate between the soil and the grass blades. When it is more than 1.5 cms, it will start to harm the lawn as it will prevent water and fertiliser getting to the roots. Dried thatch will cause dead patches in the summer.
Dethatch every two or three years when the grass starts growing again in late winter or early spring. Wait until the weather warms up and your lawn is green. You will need a professional renovator or dethatching machine. Mow the lawn short twice over. Then drive a vertical lawnmower over the lawn in both directions and then diagonally; start with the highest setting, then lower the blades. This will remove most of the lawn, although you can do this in stages.
Rake up the thatch and put it in a sack for the bins - it does not decompost. Evenly sprinkle on a fast-acting fertiliser at the rate of 3 kilos of sulphate of ammonia to every 3,000m² either by hand or with a spreader. Finish by thorough watering and keep well watered until the lawn is completely regrown.
Alternatively, you can get a professional gardening firm to carry out the work.
For cool-season lawns which are still growing quickly in February keep watered. Mow frequently with short blades to 5 cm. Fertilise every six weeks. Top the lawn with fine-textured organic soil in order to increase the humus content.
This is a great time to dig and prepare the soil for plantings in March and April.
If you have come across any bare-root asparagus or artichokes, these can be put in now. You could also try a last minute planting of lettuce, broccoli, cabbage and spinach.
As for asparagus, you could try growing it from seed in March. Soak the seeds for 48 hours before planting 5cm deep, 8cm apart in drills 30cm apart in compost enriched soil. Transplant when seedlings are large enough to handle to a well prepared bed enriched with rotted compost. Rows should be 1.2m apart with plants 46cm apart. The difference is that you will have to wait three years instead of two before you can harvest.