AS Valentine’s Day approaches and thoughts turn to how to go about wooing a mate, I’ve been watching a pair of long-tail tits begin their courtship process.

These delicate little birds are one of Britain’s earliest breeders. They begin pairing up in late January and early December and by Valentine’s Day many of them have already begun nesting.

You often see the courting couple chasing one another through hedgerows at this time. Both male and female birds have a soft, pinky plumage and together make a very "pretty" pair – and excellent subjects to paint.

Touchingly, once they have paired up, the male and female will build their nest together and seem to be very cooperative mates.

I like to think that the long-tailed tits that currently feed in my garden are descendants of some of the young that I watched grow up in their nest here two years ago.

I had seen the adult pair collecting cobwebs from my studio window. They were checking every crevice and overhang with interest and at first I had thought they were looking for insects.

But by the time they had made their third trip to the greenhouse, I suspected something else was up. I got out my binoculars and camera and opened the door to the studio so that I was ready to watch more closely when they next visited.

With the door open it was a bit chilly to say the least, but I wanted to hear them coming so I pulled on another jumper and carried on painting as I waited.

Long-tailed tits have a very musical contact call and tend to fly together in family groups or pairs, keeping in touch continually, so they are easy to locate once you learn the sound.

After a short while I heard this distinctive tune and looked round to see them bobbing along the hedge, taking short flights.

I picked up my binoculars and watched as they began investigating the greenhouse again. They were picking at spiders’ cobwebs in the overhangs and carrying the webs off towards the valley beyond the garden.

After watching these almost continuous trips back and forth, I couldn’t resist having a look to see where they were taking the cobwebs. I set off in the direction the long-tailed tits had headed and waited.

It wasn’t long before I heard them in a hawthorn hedge along the bottom of the valley below my studio. They were well-camouflaged in the thick hedge, despite the lack of leaf cover.

I crept closer and peered in with my binoculars. I could see them busily building a nest.

Long-tailed tits weave a soft, delicate nest out of lichen, moss or sheep’s wool. They were using the sticky cobwebs to stitch it together. I had heard of this technique before and understand that the long-tailed tits choose to do this because so that the nests can expand as their chicks grow.

But it was fascinating to watch them as they constructed the nest. It started off as a cup-shape, like most nests, but then the pair built it up into an elongated oval shape.

I watched over the next few days as they built up the intricate dome. Once this was complete they went on to line the nest with feathers.

In a good year long-tailed tits can have up to 15 chicks in a brood so the nest needs to be quite spacious with scope for expansion as they grow.

I was glad I had left the cobwebs in the greenhouse for them and not ventured a spring clean. When I showed my daughter Lily how the cobwebs made the nest stretchy to fit the growing family of long-tailed tits, she decided to collect more cobwebs for the pair.

Soon she had made a series of little cobweb bundles, tied up like Red Cross parcels, for the long-tailed tits and left them in the garden. I like to think the birds made use of them and the courting Valentine couple that I’ve been watching in the garden grew up in a nest made from our greenhouse cobwebs.