The publication reported that 2010 was a tough year for the industry because cold weather and "stalling economic recovery" caused trade to "slip back slightly" in 2010.
The HTA's Retail Business Benchmark survey found that trade for 2010 was down 4.3 per cent on 2009 and 2.3 per cent down on 2008.
The Future Foundation predicted a decline in real disposable income of 0.7 per cent in 2011. But it said 58 per cent of British consumers had used their garden to socialise with friends and family in the past year.
This had provided opportunities for categories such as garden furniture and outdoor leisure, it pointed out. The HTA said the royal wedding in April, grow your own and school gardening will drive the market going forward.
HTA marketing director Andrew Maxted added: "The weather in 2010 certainly took the shine off what might otherwise have been another golden year for the industry. As we gear up for 2011, we must all be aware of the economic challenges but also the many opportunities to create a more meaningful dialogue with our customers."