Big demand from supermarts signals organic boom time
Big demand from supermarts signals organic boom time
Production of organic potato
seed must increase 20-fold
if supermarket demands
are to be met with UK
produce in five years time.
Andrew Swallow asks an
organic seed producer
whats involved
SUPERMARKET plans for organic potato sales mean UK production must rocket – and organic seed production must keep pace. A Somerset seed grower and merchant says demand already outstrips supply.
"The growth in demand from supermarkets is almost too fast," says Laurence Hasson, of Learys Organic Seed Potatoes. Retailer plans to increase sales from less than 1% to 20% in just five years mean booming demand for organic seed.
That is set to rise, as Soil Association rules come into force. Currently, growers may use conventionally produced seed if organically grown seed is unavailable. But from Dec 31 2000 seed for organic crops must come from organic sources.
Mr Hasson had contracts with four organic seed growers this year, with crops of 2-8ha (5-20acres), plus his own crop in Somerset, on the Bindon Hills. Expansion plans next spring could see this contract area double, growing crops on organic registered land from Cornwall to Scotland.
"Even if crops dont sell as seed, I have a huge demand for ware and processing markets. Currently organic ware produce is making £320/t."
Concern over growing potatoes without the security of agro-chemicals is understandable, but given the right approach, consistent yields are possible, he maintains.
"Geographical area is important, as we rely on climate to reduce aphid activity and fungal diseases. We tend to stick closely to the formerly designated areas in England. The location of seed crops is the critical point. High altitude, windy sites which are isolated from other potato crops are ideal."
Prospective growers are visited to check out the site, and also the farm facilities. Producers are paid by the bag for certified seed, so access to storage and grading facilities is also important.
Health status of the seed grown largely depends on that of the input seed, so the highest grade possible is used. "We start with conventional super-elite, or even VT, depending on whats available for the varieties we want to grow." Scottish seed is preferred, but imported seed may be used when no UK equivalent is available.
Seed-bed preparation is important, providing the first stage of weed control, says Mr Hasson. False seed-beds are prepared to chit and remove weeds during the autumn and early spring.
Farmyard manure or compost is normally applied during winter for fertility. This year his own crop received 37t/ha (15t/acre) of organic compost.
Late planting, from mid-April onwards, aids weed control and ensures crops establish rapidly. Warm soils put less stress on the tuber or young plant, he notes.
"Tubers should be at a lower temperature than the soil at planting. My preference is to keep seed in the cold store at 2-3C right up to a week before planting."
Weeding post-planting typically involves two passes with an inter-row cultivator, followed by a final re-ridging when the crop is about 23cm (9in) tall.
"Timing is really important. First pass with the cultivator must be with weeds at the 2-3 leaf stage, ideally on a hot, breezy day. Once the weeds are deeply rooted you have lost the battle with mechanical controls."
Mr Hasson has developed an additional weed control technique through experience. "The weakest point for mechanical weeding was often the top of the ridge, resulting in a Mohican of weeds. Now we use a power-harrow set at 1-2in on a low PTO speed, to knock the tops off the ridges, just before emergence."
Irrigation is not a priority with seed crops as growers are not aiming for large tubers. "It can also exacerbate disease," he adds.
For most conventional growers blight control is considered the biggest risk of organic potato production, says Mr Hasson. But organic growers have learnt to live with the disease, he believes.
Copper oxychloride may be used in response to a recognised blight risk, though that stops the crop bulking, he notes. Control must be aided by the geographical area and location, making disease establishment difficult.
If 30-40% of plants are affected by blight and weather remains favourable for disease development, Mr Hasson defoliates. "It is important to prevent transfer to tubers, even if some yield is lost with early topping."
Crops with less disease are defoliated when most tubers reach 35-55mm. Some varieties may require a smaller grade of 25-35mm, particularly for continental seed markets, he notes.
A minimum of three weeks is allowed for skin-set, and to allow top infection to die back. Allowing much longer can let weed growth become a problem, he cautions.
For lifting, a manned harvester is preferred, so infected or damaged tubers can be removed in the field. "It is better to take time when lifting and get it right. It is a high-value product, which has to go into store in good condition. We cannot rely on chemicals."
Drying is essential, but curing periods can increase the risk of rots developing if an occasional infected tuber has slipped through grading. Any risk and stores should be chilled straight down to 3C.
Generally, contract grown seed is re-graded and bagged out of store on the growers premises and delivered direct. That means storage is required until Mar-April.
Price paid to the grower is based on the organic ware price, plus £30-50/t premium, dependent on variety and grade.
of seed produced.
Typical gross margin
Inputs £/ha £/acre
Seed (S.Elite) 865 350
Cultivations 100 40
De-stone and Planting
(Contractor costs) 300 124
FYM (Contractor spreading cost only) 50 20
Blight Sprays 90 36
In-crop cultivation (weed control) 45 18
Harvest (Contractor) 490 200
Roguing 62 25
Inspection cost (£310 for
5.5acres 138 56
three varieties)
BSPB royalties 158 64
Cold Storage (50t space,hired 28weeks @ £1.50/t) 900 364
Grading out of store
(£10-20/t, seed only) 225 91
TOTAL 3423 1386
Output
Seed sales (15t/ha @ £280/t) 4200 1700
Ware sales (7.5t/ha @ £240/t) 1800 730
Total Returns 6000 2430
GROSS MARGIN 2577 1044
NB. Figures based on 97 crop
Learys organic seed
crops 1998
First Early
Accent
Home Guard
Premiere
Aminca
Pentland Javelin
Second Early
Nicola
Estima
Marfona
Maincrop
Desiree
Romano
Sante
Remarka
Cara
Arran Victory
Pink Fir Apple