Nurseries that supply garden centres with plants say they face financial ruin because because of the coronavirus pandemic.
More than £1 billion of plants are facing the compost heap because the garden centres where they would be sold are now closed.
And despite an upsurge in online shopping for garden products, the industry body the represents wholesalers says it isn't enough alone to solve the crisis.
Wholesale growers Newey, near Chichester, says they face making it through the winter as a business "withhout having had any revenue at all."
Alex Newey said: "When everything gets back to normal the pubs will still be able to sell beer, the airline industry will still have aeroplanes in which you can fly people around the world, but the ornamental horticultural plant industry will have no plants, they'll have all have gone in the bin.
"Our real challenge is our till won't start ringing again until next March."
Newey's concerns are reflected in the experiences of growers across the region.
"We grow about 200,000 geraniums, 50,000 new guinea impatiens and deliliahs," says Marcel Franke, director of Staplehurst Nurseries in Kent.
"If this carries on we will probably have to dump 95% of them once its ready to because we sell it onto our garden centre customers and they are all shut."
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The Horticultural Trades Association, which represents nurseries and plant wholesalers, is based in Didcot.
Chairman James Barnes says "more than 500 million plants" face being thrown out.
"If you were to plant those out in the normal way that cover an area the size of Liverpool.
"There is simply a scale and logistics thing here that although mail order would help it does not go anywhere near solving the problem."
The association is now calling on the government to provide more support.
Mr Barnes said: ""We are calling for the Government to work with the HTA, as the industry's representative body, to come up with a financial support scheme to help those businesses which have had to scrap perishable stock and are facing a huge financial crisis."