15 January 1999

SPUD GEAR FINE FOR DAFFS

The eastern counties are as renowned for daffodil bulb

production as they are for intensive arable farming.

Geoff Ashcroft sought a Norfolk growers views on

producing these brightly coloured flowers

WITH a seed cost of up to £9000/ha, its unlikely that field after field of daffodils will dominate the countryside on the same scale as wheat and barley crops.

But in the eastern counties, there are those who see growing daffodil bulbs as an additional means of utilising idle potato equipment. And Chris Nattriss who manages the 1200ha (3000 acres) Lexham Hall near Swaffham, Norfolk, is one such grower who dovetails 31ha (78 acres) of daffodil bulbs with potatoes.

"We can use the potato harvester and insulated store in the production of daffodil bulbs," explains Chris Nattriss. "Like potatoes, we grow bulbs in 72-inch beds – though a dedicated bulb planter and grading line are used."

And when the logistics of growing the crop are unearthed, the significance of using existing machinery becomes very clear indeed. A seed rate of 15t/ha at a cost of about £500-600/t means on just 31ha, over £230,000 of bulbs are in the ground at Lexham Hall.

"Producing bulbs ties up a lot of money – and the crop needs chemical and fertiliser inputs long before harvesting takes place, 20-months later," he says.

In the eastern counties daffodil production is based on a two-year-cycle, so 50% of the total acreage is harvested and replanted each year. And growing seven varieties – all with different flowering dates – means roadside flower sales for Mothers Day and Easter are rarely a missed opportunity.

"The first years flowers are left to die off, as the quality for cropping is never very good. In the second year of growth, flowers are cut and sold, and this helps to prepare the crop for harvesting."

Bulb lifting starts with a vengeance at Lexham Hall in July, with yields expected to reach 30t/ha – double the original seed rate. And about half the yield will be retained as seed for the following crop.

"The bulbs are at their most vulnerable when they are out of the ground, so its important to grade, sell and replant as quickly as possible."

Once lifted, the bulbs are passed through a barrel cleaner on their way into Lexham Halls 1300t potato store, where it takes five days at an ambient temperature of 35íC using an under-floor system to get the bulbs dry enough for safe handling and storage.

"Airflow is critical in-store for safe drying to prevent the ingress of bacterial disease," he says. "Once the bulbs are dry, the heat is switched off so cooling can take place.

"Cooling takes place overnight using ambient air to bring the temperature of the bulbs below 18íC and out of the danger zone. Between 18íC and 29íC, the bulbs are vulnerable to all manner of storage problems," he warns.

"Changing humidity levels and incorrect air velocity can lead to Rhizopus, basal rot and neck rot – you could lose a significant proportion of the crop very quickly."

Once dried, each variety of daffodil bulb is virtually unidentifiable from the next. And to avoid confusion, Mr Nattriss has devised his own system of traceability to ensure customers get the bulbs they requested – and also the same varieties, when boxed, are replanted together.

"Its no good selling white daffodil varieties to customers who asked for yellows."

After drying, the crop is passed over a long-slot grading line, with like-sized bulbs graded into one-tonne potato boxes.

"The largest and smallest bulbs are retained for our own seed stock, with the remainder packed into 25kg nets and sold to wholesalers – and, like sending coal to Newcastle, some of our bulbs even get exported to Holland," says Mr Nattriss.

From here, bulbs destined for replanting undergo a sterilisation process for prevention of bulb eel worm and narcissus fly attacks – and sterilisation too, is a process as critical as drying and cooling.

A 20,000 litre vat containing a cocktail of formaldehyde, storite clear and a wetting agent ensures each batch of six, one-tonne boxes is thoroughly sterilised for a period of three hours. Automated controls and a diesel burner keep the sterilising solution at a constant 44.4íC, then each completed batch goes straight to the planter.

At Lexham Hall, the whole bulb production process – from harvesting to planting – is completed within six weeks, then its straight into the potato harvest.

"Its a crop which needs nerves of steel, attention to detail and generous amounts of patience to grow. It could explain, perhaps, why we only grow 31ha of daffodil bulbs." &#42