Spring seeds special – Check market needs before sowing peas

First-time pea growers must be aware of their chosen markets’ quality requirements before deciding on their agronomy, advise PGRO experts.

Marrowfats, which can command £250-300/t, must be free from marsh spot, insect damage and impurities, and have the ability to soak and maintain good colour after harvest, says technical officer Stephen Belcher.

“The premium snack food market needs up to 15,000t a year. Other outlets are in catering and for frozen and mushy peas, making a total requirement of 60,000t.”

Large blues and whites, for which demand is 110,000t a year, also go for human consumption in cans and for micronising.

“The top yielding choice is white-seeded Mascara, at 5.2t/ha. But the blue pea Prophet is only just behind,” says Mr Belcher.

Sakura is highest yielding marrowfat, at 4.5t/ha, closely followed by Genki and Falstaff. “But Kabuki is widely grown, while Bunting and Maro both have particular markets.”

Combining peas must be drilled when conditions are right, stresses colleague Jim Scrimshaw. “It pays to wait for good soil conditions. Peas don’t like compaction or very wet soils.”

Recommended populations are 65 plants/sq m for marrowfats, 70 for large blues and whites and 75-110 for small blues. “The higher end of this range applies to Zero4, the very early variety,” says Mr Scrimshaw.

Weed control options are limited, with 3.3 litres/ha of Stomp (pendimethalin) fast becoming the backbone of spray programmes. “It should be applied as soon as possible after drilling. Be aware that if it’s wet when you spray, the peas will emerge looking deformed. However, they soon grow out of it.”

Blois (trifluralin + linuron) may not be used after March 2009, he warns. “Centium (clomazone) is expensive, but has a useful place in mixes for pre-emergence cleavers control.”

Skirmish (isoxaben + terbuthylazine) and Nirvana (imazamox + pendimethalin) are other pre-emergence options, with Skirmish also having a post-emergence role for volunteer oilseed rape control, he notes.

Basagran (bentazone) can be applied from three nodes, while the hormone herbicides are a further choice. Impetus (MCPA + MCPB) can be useful for fat hen and field parsley.”

Grass weed control can be achieved from several graminicides, including Laser (cycloxydim), Falcon (propaquizafop), Fusilade (fluazifop), Sceptre (quizalofop) and Aramo (tepraloxydim), he adds.

Pests and diseases to watch out for include weevil and pea aphid, while both leaf and pod spot and botrytis can be troublesome in wet seasons.

“The weevil is a seedling pest,” says technical director Anthony Biddle. “It’s worse in cold, dry springs and is responsible for the u-shaped notches that appear on the seedlings as the adults feed. These then lay eggs and the resulting larvae feed on the root nodules.”

An early pyrethroid spray disrupts egg laying. “Get it on as soon as the notches are seen,” he urges.

Pea aphids, arriving in crops from early flowering onwards and transmitting virus, can cut yields by 30%. “Spray when 20% of plants are infested. There are no resistance issues with current insecticides.”

Fungicides are needed only in wet summers, advises Dr Biddle.

“There are no curative fungicides for botrytis and leaf and pod spot, so you should apply them if the weather favours these diseases.

“Our recommendation is to spray at first pod, and again a fortnight later at flat pod. Amistar (azoxystrobin) + Bravo (chlorothalonil) is a good mix, although Alto Elite (chlorothalonil + cyproconazole) is a better choice for the second spray on marrowfats which may need powdery mildew protection.”

Marsh spot arises from manganese deficiency, affecting processing and seed quality, says Dr Biddle. “It can be an issue with marrowfats and growers should treat crops when symptoms are seen.

“Manganese sulphate at 5kg/ha is effective – treat at first pod and repeat this 10-14 days later. Consider a third treatment in a wet season.”

Following guidelines

Lincolnshire grower David Hawes achieved excellent results with peas last year by following PGRO guidelines.

He grew 57ha of Prophet and 32ha of Bunting, recording yields of 5.6t/ha and 4.5t/ha, respectively.

Ploughing followed by cross cultivation was carried out in the autumn on the farm at Stubton, near Newark, the peas being sown with a Simba drill on a stale seed-bed in spring.

Seed costs were high at £150/ha, but weed control expense was low with a single pendimethalin spray at 3.3 litres/ha costing £21/ha. “We were lucky with ideal moist seed-bed conditions, so the herbicide worked well,” says Mr Hawes.

His two fungicides cost £54/ha and two insecticide sprays £25/ha. He also had to desiccate adding £35/ha.

The gross margin for both crops was close to £1000/ha, he says.

“There’s good demand for quality samples of peas. We followed all the rules and stuck to the recommended spray timings, which paid off.”