The Yorkshire-based inventors will be on BBC2’s Dragons Den on Sunday 30 September for more than 10 minutes as they present their invention.
Mike Smith invented the product 15 years ago to triple the capacity of any normal wheelbarrow. He and his son Joe are now trying to sell to gardeners and equestrians.
They asked for £50,000 for 10 per cent of the company but the Dragons demanded 50 per cent and after much argument, the Smith’s left empty handed.
Joe said: We got two offers for £50,000, one from Hilary and one from Duncan. They offered to split it as well but wanted 50 per cent so we said no. Deborah Meaden would have offered too but my father is a landscape gardener and was too difficult to deal with. He’d never watched Dragon’s Den before - he thought Alan Sugar was on it.
He ended up having a big argument with Deborah Meaden. She was dealing with a Yorkshireman who has had 30 years in gardening. In the end it wasn’t worth - it’s just a TV show."
Joe Smith said sales are going well with Homebase taking 5,000 units in 2013 and Tesco Direct also listing the £12.99 product.
At trade show Glee this month, Greanbase had "outstanding interest" from B&Q, Garland, Decco, Selection Marketing and catalogue companies. Greanbase took 2,000 orders and were asked to quote prices for 8,000 more units.