National Vegetable Society

"Advancing the culture, study and improvement of vegetables"

Strawberries by Martin Welsh


Latest Article

Tomato Yellow Peach

This year I tried the "Heritage" tomatoes offered as plants. Not all the plants supplied survived and grew but of those that did one cultivar, Yellow Peach, seemed to me to be outstanding.

more ...

Strawberries, a fruit which I hope you all enjoy, are one of the most recent fruits to have been bred to modern standards. With the possible exception of hybrid berries, they are one of the only fruits to rely on man’s deliberate crossing to produce the modern dessert fruit.

Wild or woodland strawberries, Fragaria vesca, have occurred naturally in the British Isles since the ice age, their range extending throughout Europe, Lapland, Iceland and to some eastern parts of the North American Continent. The fruit of these strawberries is normally small but of excellent flavour and may be gathered for making good quality jam.

For many centuries gathering of these strawberries took place without any recorded efforts being made to bring them into controlled cultivation to improve either their size or their quality. It was probably during this time that they acquired the name strawberries from the practice of threading them on straws whilst harvesting them, or possibly from the term ‘streabariye’ used by the Benedictine monk Aelfric in AD995 to describe the staying habit of the runners. Certainly the name strawberry was used long before the practice of placing straw around the fruiting plants became widespread.

Some wild strawberries were taken into cultivation, improvements in berry size were achieved, but more importantly the Dutch began to control the fruiting season by planting at different times so that the harvest period could be extended to nine months of the year. These were known as Boskoeper from plants gathered in the Boskoop woods near Haarlem. In the middle of the sixteenth century attention was paid to the Alpine strawberry, F. vesca semperflorens, which proved slightly larger berries and as its name indicates, was not daytime sensitive so was able to produce fruit in sheltered areas of the British Isles up until November.

In the seventeenth century the Hautbois made its appearance from central Europe the berries being small of a tapered oval shape, were aromatic and with a good, slightly musky flavour. They did not crop very well requiring male and female plants, but a number of different varieties did appear such as Prolific, Apricot and Framboise in France, Globe and Prolific in England. Also in the seventeenth century the Virginian Strawberry, Fragaria Virginiana, was discovered and shipped to Europe. These plants grew prolifically in Virginia producing larger berries than the woodland plant with a rather pronounced neck and a sweet scent but susceptible to virus infection.

Few varieties have stood the test of time the only survivor being Little Scarlet which is grown for its delicious flavour, fine scent and berry shape retaining properties when made into jam.

In the eighteenth century samples of the Chilean Strawberry, F. chiloensis, were collected on the Ile de la Conception in Chile and sent to France. One of the runners from this shipment was interplanted with Hautbois and Virginian Scarlet at Brest to form the nucleus of an industry which still flourishes there to this day. F. chiloensis plants found their way to England but found little favour as they required pollination producing pale fruit with a bland sweet taste and not very hardy. A derivative was however produced in France at this time which was variously called F. grandiflora, F. ananassa, or The Pine. This derivative could be produced reliably from seed, being noteworthy for its size and its distinctive pine flavour.

In 1817 Michael Keens, a market gardener at Isleworth, introduced the Keens’ Imperial a chance seedling probably from F. virginiana x F. chiloensis x Hautbois. From this chance seedling and others which followed closely on it, the modern hybrid large berried plants were developed.

Royal Sovereign was introduced by Laxton in 1892. Modern breeding seeks to emphasise many different attributes of the hybrid strawberries some endeavouring to engineer the cropping season, some producing fruits with a good shelf life, some producing plants with mechanical attributes that make picking easier, (fruit standing on perpendicular stalks, or fruit on long horizontal stalks which ripen clear of the plant) and some seeking to develop varieties with disease resistance.

Cambridge Favourite, which at one time was 70 per cent of the commercial market, was developed by D.Boyes during the 1930’s at Cambridge. Mr Boyes also bred Cambridge Vigour to provide early crops in protected cultivation. At Auchincruive Robert Reid bred plants which were particularly disease resistant producing Talisman and Red Gauntlet in the 1950’s. In Europe Gorella and Tamella were raised in Holland, Domanil was raised in Belgium and many other varieties such as Pantagruella are still being produced.

The Scottish Crop Research Institute has produced a range of plants, all of which have a musical name, Rhapsody, Symphony, and Concerto. Autumn cropping plants are particularly sensitive to temperature and day length; it is unusual to get autumn cropping varieties to do well in Scotland.

Cultivation of Strawberries

Cultivation of strawberries is not difficult. They respond well in a sunny location if a little care is taken in feeding them, and keeping the growing area clean. Strawberries in shade produce a lot of leaves but very few berries! Propagation is normally carried out by pegging down runners at the first node, so that this node forms a second plant by thrusting roots down into the soil. After a few weeks when it is firmly rooted, the runner may be cut free from the parent plant and relocated to its new growing position. If the runner continues to grow beyond the node whilst the roots are forming it should be cut back to the node.

This process should be carried out so that the plants are replaced every three years, but if the parent plants are carrying any virus disorders these disorders will be passed to the rooted runners. If virus infection is suspected, all plants should be removed and certified virus free replacement stock must be planted. Runners from early varieties can be grown in a cold greenhouse, either in old grow bags, containers or borders.

Fruit may be expected in early June. Fruit from the parent plant outside will follow at the end of June, if cloches or fleece protection is used. Fruit from main crop and late varieties taking the season towards the end of August. Commercial plant producers now store runners/plants in controlled temperature conditions so that they can guarantee the purchaser will be able to pick a guaranteed minimum quantity of fruit from each plant within a certain number of days from planting It is a matter of choice whether a straw bed is laid beneath the ripening berries.

If protection is put under the fruit, either straw or plastic film or matting, make sure that there is no risk of the roots of the plants becoming short of water or the fruit will not swell and the plant will be severely weakened. After the plants have cropped, the bed should be cleared and cleaned. Some people who use straw put a match to it. Some people go over the beds with a rotary mower.

The purpose is to remove all the old leaves and fruit bearing spurs without damaging the ‘eye’ or centre of the plant which will then put up new growth. During the winter the bed should be lightly cultivated without disturbing the shallow feeding roots of the plants, and fertiliser applied in time for the new crop. (1 to 2ozs per square yard (60gms per square metre) of Growmore 7:7:7 or similar) Plants will not do well if they become too dry or waterlogged, on free draining soil a mulch of organic manure in the spring will retain moisture during the cropping season.

Strawberry Problems

In the North East there are three enemies of strawberries: botrytis, redcore and virus. Botrytis, mouldy berries, is caused by soil and wind borne spores infesting the blossom. The best cure is to clean the bed and the surrounding area during the winter with a strong fungicide. This will reduce infestation to a tolerable minimum or eradicate it completely. If mouldy berries do appear, spray flowers with a systemic fungicide and dispose of mouldy berries without spreading more spores.

Redcore is a fungal disease of the roots, which have red centres when infected. The symptoms are listless and dying plants: the prognosis is by cutting or breaking root members and looking for ‘red core’. The treatment is to remove and burn all plants whether sick or healthy. The cure is again a drenching of the bed to a depth of six to eight inches with a strong fungicide, followed by replanting with certified virus free stock. The last disorder, virus, is recognised by listlessness without discolouration of the root members, and leaf discolouration or distortion. If virus is suspected all plants should be removed and burnt before clean replacement stock is planted.

Slugs will travel miles for a ripe strawberry, closely followed by every blackbird ever hatched, so some form of protection is called for if fruit production is to succeed If protection is erected to keep flying predators at bay slug pellets will succeed in keeping the slugs in check.

Strawberries are very flexible plants which carry a distinctive leaf and will provide some ground cover. unlike other so called ground cover which is not 100% effective, strawberries will reward the diligent weeder with a nice ripe berry. Strawberries will find a place in most borders, and they may be grown in containers for a seasonal display of flowers or berries, but however they are grown if berries are to be harvested beware of birds.

This article originally appeared in the Members Bulletin, the journal of the National Vegetable Society, which is sent quarterly to members. You can Join the National Vegetable Society here

Web NVS Site