Strawberries are easy to grow in the home garden. Photo / Supplied
Winter this year has been characterised by the immense amount of rain and grey days that we have had. The soil is sodden in lower lying areas from month after month of rainfall.
While we have been wetter than usual, we have maintained the ongoing trend for a warmer winter with few frosts here in Whanganui.
It is great this week to have a few more days of sunshine coinciding with September 1, the official beginning of spring, a favourite time of year for many as it marks the start of warmer weather. The movement into the spring season, with trees bursting into leaf and spring blossoms coming into flower, is noticed even by those not keen on gardening.
For those with an interest in gardening there is lots to do during the spring season. Lawns, vegetables, flowers and weeds all have something happening with the change of season. Spring is the time to prepare soil and garden areas for planting as well as pruning, spraying and sowing seeds. This is to take advantage of the expected warm weather over the next three seasons.
This week we are looking at growing strawberries. Berries are a treat prized by many people. They are healthy and delicious and often can be expensive to buy in the supermarket. Being small and soft, they are time-consuming to harvest commercially which contributes to making them expensive.
However, berries are very easy to grow in the home garden. Growing berries at home can be achieved in a garden of any size. The growth habit of berries is smaller than that of many fruit trees; this makes them well-suited to growing in pots and containers.
What is referred to as berries is diverse in itself. The most popular berries to grow include blueberries, strawberries, raspberries, boysenberries and thornless blackberries. Lesser known but still popular are the gooseberry, mulberry and elderberry.
Strawberries are the focus of today's column. Strawberries are quick to give results - if they are planted now, you can be harvesting fruit from mid-November through into the summer months.
Strawberries certainly fit into any size garden and grow well in pots and containers. If you are planting strawberries in pots make sure you use a specialty potting mix such as Tui Strawberry Mix.
The biggest factor in growing good strawberries is site selection. The plants need a sunny position and well-drained soil that has good structure. When planting strawberries in the garden the addition of compost, Tui Sheep Pellets, Yates Dynamic Lifter or Tui Strawberry Mix will help improve soil structure and, by bulking up the soil, can give height to the bed that will aid in good drainage.
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. As the days shorten in autumn, flowering is also initiated and small crops may be produced. Camerosa and Ventana are good short-day varieties.
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. Cabrillo, Albion and Aromas are good producing day-neutral varieties.
While strawberry plantings can be made year-round, planting done in the cooler months tends to result in heavier cropping than plantings made in warmer months. If they are planted too late, closer to the longest day (December), they will tend to produce an abundance of runners instead of fruit.
Having a short-day variety growing will give an early crop from October to January. Then from December to March, Cabrillo, Albion and Aromas, the day-neutral varieties should be fruiting. Having both short- and day-neutral varieties will give six months of strawberry harvesting.
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, such as pea straw, will help to keep the fruit clean. 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 and making fruiting earlier and keeping the fruit clean from dirt.
Strawberry plants will produce significantly more fruit if they are watered regularly and fertilised with a specially blended fertiliser such as Tui Strawberry Food.
Strawberry plants will produce good crops for three years after which time 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 fruit production in the subsequent year if these runners are removed before they grow too much as 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. Plants should then be fertilised in August or early September.
Strawberries are relatively pest-free, though during spring keep an eye out for slugs which may eat the new leaves.
Bird control
Bird control is essential when growing strawberries and it seems this is the area 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 our yummy berries.
The netting also needs to be secured around the base to prevent side entry by birds; the use of bricks or similar is effective in weighting the netting to the ground.
There are a number of different frame options, from bending No 8 wire or steel into hoops to making a "square" frame with garden stakes.
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 then plant more.
For more gardening information visit www.springvalegardencentre.co.nz
• Gareth Carter is general manager of Springvale Garden Centre
'It has been challenging but it was important to see it through.'