Gardening: How to grow strawberries at home — Gareth Carter

A rule of thumb is to plant five strawberry plants for each family member, writes Gareth Carter.

Gareth Carter is the general manager of Springvale Garden Centre in Whanganui.

OPINION

Strawberries make a delicious summer treat with icecream, they are a great addition to smoothies, and go well in numerous desserts.

Enjoyed by many, strawberries are one of the easiest and most rewarding berry fruits to grow. Plants purchased from the garden centre generally give three years of good fruiting before the yield reduces and should be replaced. In that time each plant produces a multitude of sweet, delicious fruit that far outweighs the effort and cost to set up a strawberry patch.

While strawberry plantings can be made year round, planting done in the cooler months tends to result in heavier cropping than those made in warmer months. If they are planted too late, ie closer to the longest day (December), they will tend to produce an abundance of runners instead of fruit.

For the best strawberries, plantings should be made from late autumn and during winter.

Understanding the varieties

Strawberry varieties fall into two main categories — short-day varieties and day-neutral varieties. The biggest difference is that the fruiting peak falls at a different time, so if you plant a mixture of these varieties you will be harvesting fruit for a longer period.

Short-day varieties initiate flowering when, as the name suggests, the days are short in winter and spring. Subsequently, the bulk of the fruit of these varieties will start in early November, mostly finishing after Christmas. Some seasons, as the days shorten in autumn, flowering is also initiated and a small crop may be produced.

Camerosa is a short-day variety. It produces large, well-flavoured fruit right around Christmas. It is a real winner. Another is Ventana. A new one available this year is Warrior.

Day-neutral varieties, in contrast, will fruit any time of the year when the temperatures are warm enough for growth. These varieties tend not to have such a large flush of fruit at once, but produce consistently for a longer period. Day-neutral varieties include Monterey, Aromas, Albion and Cabrillo. A new variety this year is Royal Royce.

Where to grow

There seems no limit to how and where strawberries can be grown, and they are fairly foolproof in that anyone can plant them and be rewarded with fruit.

They can be grown in raised beds with weed mat around them where the heat of the black cloth hastens ripening. This method keeps the fruit off the ground and therefore clean from soil. They can be grown in hydroponics, in glazed or terracotta pots, and specialist herb/strawberry planters. They are an edible option to grow in a hanging basket or they can fit in the herb garden. Some grow them along the edge of a vegetable garden and others will dedicate a spot to mass produce their favourite berry.

If you are planting strawberries in pots, make sure you use a specialist mix such as Tui Strawberry Mix — as with the success of most plants, the quality of the medium they grow in plays a significant role in the success you will experience. The strawberry mix will work to improve soil structure and, as well as bulking up the soil, can give height that will aid in good drainage. When making strawberry plantings, the addition of Ican Strawberry Food (which is blended with the appropriate proportions of NPK and trace elements) mixed through the soil will get the plants off to a strong start. Additional side dressings should be made every couple of months from October to March.

The biggest factor in growing good strawberries is site selection. The plants need a sunny position and well-drained soil that has good structure.

Mulching and feeding

Mulching the soil surface between plants will prevent weeds, maintain an even soil temperature and prevent moisture loss in summer. A mulch will also help to keep the fruit clean. Suitable mulches include straw, sawdust, pine needles, pine bark or wood shavings. However, one needs to be careful that mulch does not also result in creating a habitat for insects such as slaters, which can cause damage to the fruit.

The traditional and very effective method of growing strawberries is to cover the raised mound with black polythene plastic or weed mat, making a small slit for each plant. The black mulch attracts heat, increasing soil temperature, making fruiting earlier and keeping the fruit clean from dirt.

Cultural notes

In addition to the regular feeding mentioned above, strawberry plants will produce significantly more fruit if they are watered regularly during the summer months. This is best done in the early morning to reduce the risk of humidity build-up.

Strawberry plants will produce good crops for three years, after which the “mother” plants are best thrown out. The plants will generally produce runners each season during late summer. In the first year, it is beneficial for the next year’s fruit production if these are removed before growing too much because they will drain the plant of energy that will benefit next season’s fruit. However, in the second and third seasons, saving some runners and replanting will allow you to replenish or enlarge your strawberry patch.

For plants that are starting their second or third season, all the dead leaves from the previous season should be pruned off and removed during winter. This helps minimise the hosting of pests and diseases. These plants should then be fertilised in August or early September and then every couple of months from October to March as described above.

Strawberries are relatively pest free; just keep an eye out during spring for slugs, which may eat the new leaves, and the occurrence of aphids and mites during the summer months that may require control using bee-friendly Yates Mavrik.

Bird control

Planting strawberry plants (like other fruit trees) is a great way to attract birds into the garden. So to enjoy the fruits of your labour, bird control is essential when growing strawberries and it seems this is where many people come unstuck.

The most effective method is to construct a frame on which bird netting may be draped. The frame needs to be able to hold the bird netting at least 30cm above the plants so when birds sit on the cloth they are not able to reach through the netting and eat those precious berries.

The netting also needs to be secured around the base to prevent side entry by the birds. The use of bricks or similar to weight netting to the ground is effective.

There are several frame options, from bending No 8 wire or steel into hoops, to making a “square” frame with garden stakes, to putting an upturned pot on the top of a stake that keeps the netting held up away from the plants.

How many to plant? A rule of thumb is to plant five plants for each family member. If you want to eat bowlfuls of strawberries every night during summer, plant more.

For more gardening information go to www.springvalegardencentre.co.nz