There is nothing quite as exquisite as fresh homegrown raspberries. Tasting a homegrown plump and juicy berry, you realise that the supermarket raspberries you have tasted just don’t compare. Bought raspberries are expensive and have often been sprayed with chemicals and travelled hundreds of kilometres to get to you, leaving them lifeless and lacking in taste.
The good news is, raspberries are easy to grow and can be grown in any backyard as you don’t need lots of room. Raspberries can be grown in a range of climates but prefer cooler temperatures.
PREPARING THE SOIL
Raspberries need to be planted in rich soil that provides good drainage and has a pH of 5.5–6.5. Depending on the variety, the pH may need to be adjusted to accommodate the specific requirements of the plant. Try using pine needles to prepare the soil and reduce the pH, placing the pine needles around the base during the warmer months. This can also act as a mulch.
Raspberries need to be planted in rows running north-south to ensure even sunlight. Add lots of compost and well-rotted manure to the soil before planting. Create a long mound approximately 20 cm above ground level to provide good drainage. Depending on the variety, canes should be planted between 450–600 mm apart. July to September are the best times to plant the canes.
One of the most economical ways of propagating is to cut suckers from the main plant and strike for the following season, or to bury the suckers directly into the ground. If a friend grows raspberries they will often have suckers that you can just carefully dig up, taking care of the roots, and replant immediately. Wrap the roots of the suckers in damp newspaper to keep moist.
Create a trellis with two to three strands of wire attached securely to posts on each end. Then as the canes grow, train them along the wires.
There are a multitude of varieties of raspberries available both commercially and via retail outlets; the skill is in identifying the right variety for your area. It is likely you will need to experiment with a few varieties before finding one that is suitable.
There are two main types of raspberries, summer and autumn fruiting varieties. Summer varieties will fruit on two year old canes and autumn varieties fruit on the first year’s growth. This is important to know when it comes to pruning. If you choose a range of both varieties you can be harvesting raspberries from your garden from early summer through to late autumn.
One of the most important things to keep in mind is the required number of chill hours each variety needs. Chill hours are the total number of hours a plant is exposed to temperatures usually considered to be below 5°∆C. This ensures the plant sets fruit well.
Generally, most will need approximately 400–800 hours. If you are intending to grow in a warmer area, avoid European varieties as they tend to need more hours to set fruit.
When it comes to pruning, you need to know whether your raspberries are autumn or summer varieties.
As mentioned earlier, summer varieties fruit on second year growth. Cut down to ground level all of the two year old canes that have produced fruit, and leave the one year old canes, which need to be trellised and left to fruit next year. It is best to prune soon after fruiting so you know which canes are which.
Prune canes down to ground level. Alternatively you could try the technique of tip pruning at the end of January, two nodes down from the last fruiting flower, as this will produce a crop for the following summer.
Harvests will vary greatly depending on the weather conditions during growing seasons and harvest. The table below provides a guide only; this will vary from year to year and depend on the variety and location.
In areas of high temperatures it is recommended to provide shade for the hottest parts of the day. Shade-cloth works well and can also assist with reducing bird damage.
Harvesting ripe raspberries is best done early in the mornings as the fruit tends to be firmer. Subtle colour changes can make the difference between a perfect raspberry and an okay raspberry. Generally the darker the colour, the riper the fruit, however once the colour starts to move to a plum shade it is likely to be overripe. The flavour of an overripe raspberry is still wonderful, but the holding properties decrease significantly and they tend to bleed. Raspberries stored below 3˚C can be held for up to seven days in a punnet, depending on the variety.
Raspberries are a great crop to grow as they are most delicious picked straight from the plant. Best of all for backyard gardeners, they are relatively easy to grow in any sized space.
Steven and Anne-Marie (Annie) Jeffries from the Berry Farm grow raspberries commercially in the Adelaide Hills. Their berries are grown using organic principles.