Good Agricultural Practices
International regulations on food safety and social accountability in the production of fresh produce are becoming ever stricter. Consumers are becoming more and more particular about the quality, safety and reliability of the fresh products they buy. The main buying countries require the implementation of GAP. The GAP guidelines aim at producing a product that is safe, environment friendly and socially acceptable and of high quality. The following are the guidelines which are supposed to be implemented by the farmers and exporters.
- Keep up to date farm production records in order to maintain consumer confidence in food quality and safety.
- Apply proper crop protection strategies in order to reduce the use chemicals.
- Observe the required standards during pesticide application in order to protect the health and safety of the sprayer.
- Observe the required standards during transportation, storage and disposal of pesticides in order to minimize detrimental impact on the environment while conserving nature and wildlife.
- Observe hygiene requirements during harvesting and postharvest handling of produce.
- Adhere to regulations of wages and employment act
- Adhere to environment protection regulations.
Double digging is recommended to break the hard pan and improve soil structure. Beds should be one (1) meter wide by any desirable length with a path of 50cm wide between beds. Incorporate 15kg of well decomposed manure per meter squared. Level the beds using a rake, and water the whole bed in preparation for planting. The bed preparation should be done one month prior to planting.
Propagation and planting:
Strawberries are vegetatively propagated through splits and runners’ .Splitting is the most common method used to propagate strawberries, seeds are rarely used because most are not viable, and the few that are viable take a long time to reach a good transplanting height. Before planting work the soils so that there is deep and a reasonably loose planting bed.
- Trim the leaves
- Trim the roots
- Dip the split in a fungicide solution for 24Hr prior to planting e.g ridomil, pearl, cotaf, master,etc to prevent fungal infections
Prior to planting dip the split in clean water for 30 minutes.
Dig holes of approximately 7.5cm deep, 30cm between rows and 30cm between plants giving a plant population of 75,000 plants per Ha. Apply 2gms/hole of a recommended nematicide e.g mocap , bionematode, nembedicine etc.
The crown is very short and will not tolerate deep planting. Roots should not be allowed to dry. The middle of the crown should be level with the top of the soil. Soil should be watered after planting to set the strawberry plants in the ground (Avoid watering plants directly. Drip irrigation works best). After the initial watering, the soil will settle and the soil line should be even with the bottom of the crown as indicated in the picture.
Weed Control/Field hygiene:
At planting time, the soil should be weed free. After planting, weekly cultivation is recommended to remove weeds when they are small. Regularly remove all the diseased runners and leaves.
Avoid planting with fertilizers to avoid dehydration of the splits, since the plant goes into dormancy for 14 day. Within the first month deflower the first flowers and the second flowers to prevent premature fruiting. After 30 days fix CAN 10gms per hole in between the plants. The second month, top dress with NPK 17:17:17, 10gms (1 tablespoon) per hole between the plants. Fertilizers should be used to maintain soil fertility and maximize plant growth and fruit production. Strawberry being a heavy feeder needs to be regularly boosted with foliar feeds e.g easygrow vegetative, flower and fruit, calcium to firm the skin of the fruit and to decrease fruit deformities. Strawberries are self pollinating but cross pollination achieves a better yield.
NB: Do not over fertilizer or you will have excessive leaf growth and poor flowering.
Mulching help conserve ground moisture, keep fruit clean and adds humus to the soil. Avoid placing mulch when the plant is too young. Wheat straw or hay can be used for strawberry mulch. Do not use black plastic since it will raise the soil temperature and optimal fruit production requires cool soil.
During the cold and rainy season, the strawberries go into a rest period, at this stage all old and diseased leaves are removed off the plant to reduce infection from diseases or pests increase aeration and allow re-growth of foliage. Removed leaves should be collected and burnt outside the field. Cut off runners regularly except for those needed for planting. One or two runners can be rooted for the next planting. After seven month thin the plants to leave the mother and three daughters. The thinning can be established elsewhere.
-In the first month of establishment water daily in the evening for 30 days. This will help in root establishment and initial vegetative growth. From the second month onwards, after applying mulch, water twice or thrice a week depending on the weather. Best method of watering is through drip ,watering can or low pressure hose pipe.
NB: high pressure sprinkler cause flower abortion, fruit bruises and contributes to fungal diseases on the leaves.
Maturity and Harvesting:
Maturity of strawberries is a function of the temperatures prevailing during the growth period. The warmer the temperature the faster the maturity. Maturity period ranges from 75 - 90 days depending on the variety.
Berries should be picked when they are completely ripe or half ripe. All ripe berries should be picked otherwise they become overripe or rotten by the next picking. Avoid crushing the fruits at picking. This can be achieved by use of a clean and firm container. Pre cool the fruits to avoid dehydration and deterioration. For fresh market the strawberries are sold in punnets ( 250 gms) or in weight basis. Strawberries deteriorate rapidly after harvest. Pick fruits every two days as fruits ripen quickly. Deterioration can be slowed down by pre- cooling the berries and storing at temperatures below 40centigrade.for the small scale farmer use a charcoal cooler.
Post harvest handling:
Sorting - done in the field and involves the removal of damaged and misshapen and dirty fruits. Remove all the fruits without a calyx.
Pre - cooling; This is done to remove the field heat, to minimize deterioration. At small holder level, farmers can use charcoal coolers. For distance markets, forced air pre-cooling will be necessary.
The fruits are graded into different sizes for marketing.
According to the shape and the size
1st grade: 6 - 9 fruits per punnet.
2nd grade: 15 - 25 fruits per punnet
3rd grade: 28 - 32 fruits per punnet
Under sizes can be processed into jam or juice.
Strawberries are packed into the punnets in readiness for the market.
NB: avoid washing the fruits in the packhouse since it destroys the skin and hastens deterioration.
An average yield of 25,000 kg/ha can be achieved in the first year and 18,750 and 12,500 in the second and third year respectively. The plants should be renewed by the end of the third year.