Over the past decade the demand for garlic has steadily risen. Imports in 1987 were 4,600 tonnes representing £4m. This compares with 2,500 tonnes worth £2.5m in the early 80's. The major supplies arrive from Spain, Italy, France, Argentina and Iran. Production in this country also continues to rise - albeit on a comparatively small scale. The national area is perhaps 70 ha, say 550 tonnes. Production is concentrated in the south of the country, particularly on the Isle of Wight.
The whole operation of lifting, drying, dressing, grading and packaging for market has to be undertaken with care to avoid damage. The slightest bruising or mechanical damage allows entry of disease. This causes the main limitation on the expansion of garlic growing, because any form of mechanical handling during harvesting or dressing causes unacceptable levels of damage. Much hand labour is therefore required to market the crop.
The crop will grow very successfully in this country as far north as Yorkshire, but the best yields can be expected in the more southern areas. The only major field trials have been carried out at Efford EHS between 1981 and 1988. These concentrated on evaluating clones and varieties, spacing, time of planting, nitrogen requirement and various feasibility studies regarding handling and husbandry. The trials showed that yields up to 15 t/ha marketable bulbs were possible with attention to detail on a field scale. Many growers yields are as low as 5 t/ha, often due to a combination of poor stock, incorrect planting conditions and bad handling. It was also established that the crop quite happily survived a wide range of climate conditions over winter from autumn plantings.
growing the crop is not difficult and it will thrive on a wide range of soils, providing they are easily worked and are free draining. Maximum growth occurs around 16ºC during April and May, before bulbing commences in June. Warm sites at this period are therefore an advantage. For good yields during the maximum growth period it is important for the crop not to be short of water.
Good yields can be achieved by planting any time between mid October and early March. The main criterion is to plant when soil conditions are good.
- The cloves require a period of 0 - 10ºC for 1 - 2 months in order for the plants to bulb properly.
- Planting after early March tended to reduce yield.
- In the south, planting in February (providing soil conditions were good) has given similar yields to planting in autumn.
- Early varieties are best planted in the autumn as otherwise cloves may sprout prematurely. However, in trials, provided cloves were sound, February planting of early varieties still gave good results.
Treatment of Cloves before / at Planting
Hot water treat if Eelworm is suspected or source not guaranteed free from infestation: 46ºC for 2 hours include 0.5% formaldehyde, followed by a Benlate dip as below. (Further details of HWT available if required). If using own stocks, only use the best bulbs for splitting and handle carefully. Damaged cloves will not grow. To prevent rots, dip cloves into Benomyl (as Benlate) 1 kg/100 litres, immediately after splitting the bulbs. Some suppliers may offer this service.
Cloves weighing less than one gram are not productive. Generally larger cloves give larger bulbs. Cloves over 4 grams in weight will produce more bulbs over 50 mm diameter, but these are not always demanded by outlets.