IT has been hard to believe that spring is around the corner after this week's weather — but then I suppose it was the half-term holidays.

Last weekend I was taking photographs of snow-covered gardens in the South East, so it is perhaps no surprise to find the cold weather has delayed spring plants flowering in our gardens by as much as a month.

The prolonged cold spell has certainly taken its toll on my garden, and the body count is starting to rise as the damp also gets to tender plants like my agaves.

However, the violas and primroses have finally bucked up in the past couple of weeks — those that have survived the arrival of voracious tiny baby slugs and chomping vine weevil… which I found hard at work despite the freeze.

The dainty snowdrops are in full bloom and the hellebores are starting to look up.

But my bulbs have some way to go before flowering.

Looking on the bright side, according to the National Trust, we could be in for a blooming lovely spring as the plants held back could put on their show at the same time.

And the magnolias promise to be fabulous this spring.

Every year since 2006 the National Trust has conducted a flower count in their Devon and Cornwall gardens, including at Coleton Fishacre at Kingswear and Greenway at Galmpton.

For the first time this year other trust gardens across the country have taken part, providing a valuable record of the nation's gardens as they emerge from winter.

But while the survey found spring flowers have been delayed by as much as a month, their experts are predicting we can expect a riot of colour when spring finally arrives.

Mike Calnan, National Trust head of gardens and parks, said: "Gardens plants are the perfect weather barometers.

"By comparing the number of plants in flower across various gardens on a set day each year and tracking those changes over time, we will be able to demonstrate how our gardens respond to weather patterns and ultimately climate change."

The coldest January in 23 years has particularly affected gardens in the South West and South East with some 1,115 plants recorded in flower this year across 12 gardens in Devon and Cornwall compared to 3,335 in 2008, when the highest count was recorded.

Ian Wright, National Trust gardens adviser for Devon and Cornwall, explained: "During the last decade, warmer, wetter winters have seen spring arriving earlier and earlier, especially in the South West.

"But like last year, this year plants have been held back around two to four weeks by the cold weather but once it warms up everything will be blooming at once, rather than over a longer period of time, so we can expect a spectacular spring.

"There has also been an interesting split across the region with gardens in the west suffering more from snow damage than those in the east but everywhere saw losses due to the sustained low temperatures in January."

On the bright side, he added: "Around our region magnolias are more heavily in bud than I have seen them before, due to the wet summer and warm autumn.

"This means that when they do flower, later than usual this year, the display will be fabulous."

There was an overall decrease in the number of plants counted in Devon and Cornwall of 7.5 per cent compared to last year.

But some gardens did better than others.

The highest number of flowers recorded was at Killerton with 172 (up from 85 last year) and at Lanhydrock in Cornwall 166 (up from 153 last year).

At sheltered, coastal Coleton Fishacre volunteers found the number of plants flowering there this year was also up on last year.

There was nothing flowering out of season, though the camellias are beginning to open quite well and several groups of primroses are out.

The other South Devon gardens where counts were carried out were Overbeck's at Salcombe, Saltram Plymouth, Greenway Galmpton and Killerton near Exeter.

However, the highest number recorded was in 2008, with 3,335 plants were counted in Devon and Cornwall gardens, representing a 76 per cent increase on the 2007 total.

Nationally, the UK average temperature for December, 2009 was 2.1C according to the Met Office, making it the coldest December since 1995.

The UK mean temperature for January was 0.9C, making it the coldest January since 1987.

The National Trust gardens now open include Castle Drogo, weekends only to March 13, and Killerton, open daily, Overbeck's Salcombe, Monday-Thursday and Saltram, daily except Fri.

Coleton Fishacre will be open Saturday to Wednesday from March 1 and Greenway from Wednesday to Sunday after March 3 and Knightshayes Court, Friday to Sunday, until March 13.

For more information, log on to www.nationaltrust.org.uk