The first thing you need to know about Currants is that they are not all created equal. Black Currants (Ribes nigrum) have high concentrations of Vitamin C and anti-oxidants and fruit on what is known as the previous year’s growth or 1 year wood. Red and White Currants (Ribes sativum) bear fruit on the new seasons growth which develops on the existing network of branches. Don’t worry there is a simple explanation below. Red Currants have some Vitamin C but White Currants have none. Currants grow well in parts of NZ that have some winter chill and they don’t like summers that are too hot. If you live in a warm area of NZ grow Currants where they will get some afternoon shade.
Situation -Plant in an open sunny position in cooler areas or in part shade in warmer areas.
Soil -Currants prefer a nice deep acid soil but will tolerate clay and heavy soils as long as there is plenty of organic matter to keep the soil moist but not water-logged.
Water - As with all fruit it is important that Currants do not dry out completely in summer when the fruit is developing. Put some mulch around the roots to help conserve moisture.
Feeding - Currants respond well to feeding with fertiliser and organic matter. A side dressing of a well balanced fertiliser can be given in spring along with some extra Pot Ash (Potassium).
Cultivation – Currants have shallow root systems which means their roots are close to the surface of the soil therefore don’t go mad with the push-hoe or use weed spray close to the plants – it is probably best to hand weed to avoid root damage.
Pruning – Black Currants are usually pruned after fruiting or in winter. At the time of planting in autumn-winter prune your plant back hard, leaving just one bud above the ground. Strong shoots will develop and will bear fruit the second summer after planting. (This is usually described as 1 year wood.) The shoots will continue to fruit for a few years on any new growth but when they become weak or tired prune them hard in winter. The idea is to maintain a balance of developing new shoots and some older fruiting shoots.
Red and White Currants develop into a multi-stemmed bush with a short trunk. At the time of planting in winter cut back any branches by about 1/2. These will grow into your main branches and they will have side growths (laterals) that will fruit each season. Red and White Currants will fruit on two or three year old lateral growth so after the initial pruning at planting time you can leave them alone for a bit. Thereafter remove any old unproductive growth, usually branches that are about 3 years old. Prune back close to the main stem near a bud which will then re-grow. Prune back all side shooting laterals to one or two buds to encourage new healthy growth on which fruit will develop.
Harvesting – Currants are harvested in summer after the fruit has coloured well. Currants will hold on the bush for several weeks but any fruit nearing maturity may fall off with heavy wind or rain.
Wairere Nursery 826 Gordonton Road, R D 1, Hamilton Ph: (07) 824 3430 Email: Open 7 days 8:30am-5pm