Over the past decade the amount of beet harvested on a late season just-in-time basis has increased from 5% to 20%, according to British Sugar’s Stephen Brown.

Not all soil types will allow growers to match lifting to delivery requirements exactly, but the trend looks likely to continue.

While beet growth is very limited after December, sugar is not being lost as it would be if it were in the clamp, he says.

Typically, daily sugar loss in clamped beet during January and February is about 0.15-0.20% per adjusted tonne, says Broom’s Barn’s Keith Jaggard.

“The warmer the weather, the faster it’ll be. If beet is left in the field and doesn’t get frozen, you’ll lose virtually nothing, but if it gets frozen you could lose a lot,” he warns.

But where longer-term storage is needed, following simple guidelines can reduce the risks of severe sugar losses or rots developing, as Mr Brown and Broom’s Barn’s Mike May explain.

What if it goes wrong?

Too much soil on clamped beet can impair ventilation and cause overheating, while clamping beet that is very wet can increase rot risk, warns Dr Jaggard.

Soil-borne Violet root rot is the easiest rot to identify because of the bright purple colour beet turns before it sets in.

There are also various fusarium rots that are a bigger problem after drought-affected summers, which cause roots to crack, Mr May says.

“If you have a problem, the first thing to do is call the local factory area manager to try and arrange earlier delivery.”

Careful monitoring is vital to spot risks early.

Steam rising on cold mornings can indicate hot spots, but does not necessarily mean there is a problem, he notes.

Growers should aim to keep clamps between 5C and 10C, but while they can be protected against frost, stopping them from getting too hot is a bigger problem.

“Monitoring temperature is not easy.

It will almost always be warmer inside the clamp, but sometimes it can be the other way around because of the time lag between air and clamp heating/cooling.”

See the Sugar Beet Growers Guide, for more clamping information. www.uksugarbeet.co.uk