Growing Scrumptious Strawberries
Strawberries have always been popular. They are great tasting, and are relatively easy to grow, even in a small area. They grow well in most soil types, but prefer fertile, free draining soil.
While strawberry plantings can be made year round, planting done in the cooler months tend to result in heavier cropping that plantings made in warmer months. If they are planted too late, i.e. closer to the longest day (December), they will tend to produce an abundance of runners instead of fruit.
How many to plant? A rule of thumb is to plant 5 plants for each family member. If you want to eat bowlfuls of strawberries every night during summer then plant more!
Where To Plant
Choose a warm sunny position, sheltered from strong winds. Strawberries require a free draining soil with lots of compost. This is particularly important in lighter and sandy soils. In clay soils, raise planting beds and add lots of compost.
There seems no limit to how and where strawberries can be grown, and they are fairly fool proof that anyone can plant them and be rewarded with fruit!
They can be grown in old car tyres where the heat of the tyres hastens ripening. This method keeps the fruit off the ground and subsequently clean from soil. They can be grown in hydroponics, in glazed or terracotta pots, 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!
Many will grow strawberries in pots and containers of various forms. If you are planting strawberries in pots make sure you should use a specialist mix such as ‘Tui Strawberry Mix’ – as with the success of most plants the quality of the media they grow in plays a significant role in the success you will experience.
The biggest factor to growing good strawberries is site selection. The plants need a sunny position and a well drained soil that has good structure. Some shade during the hottest part of the day in summer appears to be beneficial. Keep the soil well watered so it remains moist but not consistently soggy. When planting strawberries, improve the garden with the addition of ‘Tui Strawberry Mix’ or ‘Tui Sheep Pellets’. These will work to improve soil structure and add nutrients, as well as bulking up the soil can give height that will aid in good drainage.
How To Plant
Work into the soil before planting, a couple of handfuls of lime and a general fertiliser, (‘Ican Organic Vegetable Fertiliser’ & ‘Ican Berry Food’ are good options). Plant on raised mounds so that the crown and roots never become waterlogged. Plants should be about 300mm apart.
When growing in pots and containers we recommend ‘Tui Strawberry Mix’. This can also be used in the garden. ‘Ican Premium Potting Mix’ is the next best thing if Strawberry Mix is unavailable.
Mulching
This is a highly recommended practice as it suppresses weeds and conserves moisture in the soil. A layer of mulch, (straw, sawdust or similar) laid on the surface in October will prevent moisture loss, benefiting the plants, and providing a clean surface for the fruit as it grows and ripens. Suitable mulches include straw, sawdust, pine needles, pine bark or wood shavings. Weed mat is an option preferred by many.
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 the fruit clean from dirt.
Varieties
Strawberry varieties fall into two main categories; short day varieties and day neutral varieties. The biggest difference being 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. Camarosa is a short day variety. This variety is produces large, well flavoured fruit right around Christmas. It is a real winner. Another is Ventana.
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 Aromas, Albion and Cabrillo.
Feeding and Maintaining
- Strawberries benefit from an annual dressing of lime or gypsum plus fertiliser at planting time, followed by an application of again in September or October. ‘Ican Organic Vegetable Fertiliser’ or ‘Ican Berry Food’ are a good options for use in garden beds or large planter boxes. Using a specially blended fertiliser such as ‘Ican Berry Food’ contains the appropriate proportions of NPK and trace elements for optimum results.
- For strawberries grown in pots and containers, a gentler, slow release fertiliser is necessary as the above options are too strong for smaller, contained areas. Try ‘Ican Slow Food’ for a stable release of fertiliser across two years. Top up with ‘Thrive Camellia, Gardenia & Blueberry Food’ – a pot-friendly, 3 month fertiliser increasing the acidity of the soil slightly which contributes to sweeter flavour in your strawberries!
- Strawberries like a good moisture level but not wet conditions. While they like to be well drained, plants will need to be watered during the summer months. Watering is best done early in the morning or at a time when foliage and fruit dry quickly as to reduce the rick of humidity build up and minimise botrytis fruit rot.
- To prevent leaf spot and botrytis (grey mould), avoid overhead watering. If botrytis is observed, then spray with ‘Botry-Zen’ – an organic, crop-friendly fungal spray with no withholding period.
Strawberry plants will produce significantly more fruit if they are watered and fertilised regularly. We recommend boosting your plants with a liquid fertiliser every week in-between watering. ‘Ican Liquid Tomato’ has the best nutrient balance for strawberries, or ‘Ican Fast Food’ is a good second option.
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 the next years fruit production if these are removed before growing too much as they will drain the plant of energy that will benefit next seasons fruit. However in the second and third season 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, just keep an eye out for slugs during spring which may eat the new leaves, and the occurrence of aphids and mites during the summer months, which may require control using bee friendly ‘Yates Mavrik’.
Bird Control
Planting strawberry plants (like other fruit trees) is ironically 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 that 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 those precious berries.
The netting also needs to be secured around the base to prevent side entry from the birds, the use of bricks or similar weighting netting to the ground is effective.
There are a number of different frame options from bending number 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, which keeps the netting held up away from the plants.