Your garden: February 4

Once delphiniums have finished flowering, trim them back to encourage more flowering in a few...
Once delphiniums have finished flowering, trim them back to encourage more flowering in a few weeks’ time. PHOTO: OTAGO DAILY TIMES
Vegetables

Onion seed sown this month will withstand the winter months, then mature into good-sized bulbs for harvesting next summer. Prepare soil with potash, lime and some garden compost, or a general garden fertiliser. Space cleared of early potatoes or peas is ideal for growing onions. Pukekohe Long Keeper, developed by Pukekohe’s commercial growers in 1923, remains popular with home gardeners, while other varieties available include Red Brunswick, Ringmaster and Odourless.

Seed of cabbage (Earliball, Green Acre or mini-variety Space Saver), silverbeet and spinach (Winter Queen, Santana) can be sown for use in early winter through to spring. Late summer and early autumn sowing is important, as they will grow rapidly in good soil before the first frosts. Sowing after a show of rain is ideal. Make sure beds do not dry out.

Weeds gallop through their life cycle at this time of year and seedlings will produce seeds in a few weeks. Dig weed plants but not docks or dandelions into the soil, or pull them out and add to the compost heap before the seeds ripen.

Second-crop potatoes, such as Maris Anchor, may be lifted now and a green manure crop sown. Green manuring involves growing suitable plants for about six months and then digging them in before they flower. Where a faster turnover is needed, mustard can be sown, as it will mature in three months. For general purposes, oats and blue lupins are recommended. Lupins add nitrogen to the soil, while oats help break up heavy soils. Field peas and red clover can also be used.

Flowers

Delphiniums, Oriental poppies, Aubrieta, shasta daisies, lupins, pyrethrums, leopard’s bane (Doronicum) and other early-flowering herbaceous plants should be trimmed now. Doing it immediately after flowering will encourage some plants, particularly delphiniums, to flower again in a few weeks.

Roses, dahlias and sweet peas can also be encouraged to flower longer by removing faded blooms.

Dahlias benefit from liquid manure as well as conventional watering. This was once made with human urine, the contents of the chamber pot diluted and tipped on to the garden. This product was considered particularly beneficial for polyanthus. More usually these days, horse, cow, sheep or poultry manure is used. A third of a 10-litre bucket of manure topped up with water is fermented for two or three weeks, then diluted to the colour of pale tea and watered on to the ground around the plants. Green material can also be used. Comfrey makes the best green mix, as it is high in nitrogen and potash, but any green weeds and lawn clippings can be used. This is also a good way to destroy convolvulus, docks, dandelions and other perennial weeds that do not rot readily in the compost bin.

Fruit

Strawberries may still be layered, choosing the first new plant on each runner and cutting off the rest. Placing compost around the runners will help roots develop. Transfer the new plants to their permanent places in about three weeks.

Dig out and dispose of all strawberry plants that have borne fruit for two or more years. Because they can carry disease, do not put strawberry plants in the compost bin.

For younger strawberry plants, trim off old leaves, clear away any weeds and give them a mulch of garden compost mixed with blood and bone and superphosphate. That prepares them for autumn growth.

Cut out old raspberry stems (canes) that have fruited. Stake or wire young canes, removing any weak, spindly or misshapen ones. Six to nine canes a plant is reasonable to supply next summer’s crop. A mulch of straw, grass clippings or compost at this time helps retain soil moisture and provides humus. Apply on ground already well saturated by rain or artificial watering.

Because they fruit next year on growth made this season, blackcurrants can have all old wood removed once fruiting has finished. Prunings can be used to propagate new plants. As an alternative to growing in garden beds, currants (black, red and white) can be grown on a fence or trellis. They also make useful shelter hedges or can screen a compost heap.

Tomatoes grown in a glasshouse or tunnel house should have any yellow or dead leaves removed. Pinch out laterals (young shoots at leaf joints) of bush (determinate) types, ensure all tomato plants have plenty of ventilation and reduce watering when fruits stop swelling and begin to ripen.

Add a Comment