Garden centre owners have expressed their concern after the possibility of hosepipe bans in 2012 became more likely.
Anglian Water is applying for a drought permit and the Environment Agency will decide whether the supplier can extract extra water from the River Nene to replenish Pitsford reservoir, now at 56 per cent capacity.
South East Water has not ruled out applying for drought permits, while Thames Water said below average rainfall this winter could pose difficulties. Veolia Water Central warned that it needed a dramatic increase in rain for the rest of winter to avoid restrictions. Southern Water and Severn Trent said they were hopeful that winter rainfall will help replenish supplies.
Scotsdales managing director Caroline Owen and Tillington plant buyer Andy Bunker both said restrictions would hit plant sales.
Anglian Water representative Ciaran Nelson said: "We saw an average 20 per cent less winter rainfall in our supply region. This was then followed by the driest spring in more than 80 years.
"That's why we're taking prudent action now, applying for a drought permit, to try to keep water supplies secure and customers' taps flowing."
Cambridgeshire, South Lincolnshire and Northamptonshire only had half the normal rainfall during September and October, while November has also been mild and dry.
North West Water applied for a drought permit in June 2010 but this did not lead to a hosepipe ban. There were widespread bans, including by Thames Water, in 2006. Fines are up to £1,000 for watering gardens when bans are in place.
In June, a revision to the UK Water Industry Research code of practice, issued on behalf of water companies, said water companies must take sensible and proportionate steps to restrict water use and communicate clearly with customers before they impose restrictions.
- Caroline owen, managing director, Scotsdales
"It is certainly worrying. We still haven't had any real rain and the garden centres that I spoke to when we had hosepipe restrictions in 2006 saw a real effect on plant sales.
"If we had more bans I would be really concerned for plant sales particularly in light of the tremendous year we have had and plant sales being the real core of our business. The HTA is talking to water companies."