At the moment I am in the hands of builders: my life is punctuated by three cups of tea a day (for them) and the air is rife with dust. So it was a pleasure to escape to the Cottesbrooke Plant Finders’ Fair, at Cottesbrooke Hall, just north of Northampton. This relaxed event is held every year at the end of June and it’s possible to turn up and buy a ticket on the day and then visit the 20 or so plant stands before wandering around the wonderful garden — winner of the HHA Garden of the Year Award in 2000. Several other excellent gardens are close by. (For more information email enquiries@cottesbrooke.co.uk or call 01604 505808.) I bought a ‘save the bee badge’ there, and as I walked round I thought about all the plants that have arrived by serendipity courtesy of the bees. They are much more effective than people. Different bees pollinate in different ways. The systematic honey bee concentrates its efforts on one type of nectar directed there by other bees who do the waggle dance. The bumble bee is an opportunistic browser with two unique traits. First, they can fly in cool weather and queens of Bombus terrestris (the Buff-tailed bumble bee) can emerge as early as January. Second, they buzz pollinate and, when they enter a flower, they shake the pollen down from the anthers.

Between them, they have provided us with plants that could never have arisen without them. The longest flowering anthemis, for instance, ‘Susanna Mitchell’, sprawls through May to July covered in lemon-yellow daisies. Cut her down and she will do it all again. Three sterile hybrid hardy geraniums also arrived as spontaneous seedlings. ‘Orion’ is a bright sapphire-blue that can flower as early as April. ‘Patricia’ is a black-eyed magenta-pink and both form a billowing mound. They can be cut back in mid-July for an autumn show. ‘Rozanne’ is a paler blue sprawler that will flower from late June until September.

Many dahlias have arisen as seedlings including ‘David Howard’, a dark-leaved butterscotch dahlia of the highest calibre. The seeds were collected from the ‘Bishop of Llandaff’ dahlia by David Howard (now a successful Norfolk nurseryman) and sown in the late 1950s. He grew hundreds of dahlias from seed on an allotment and immediately spotted its potential. As he left for National Service in 1958, his last words to his parents were “look after that dahlia and don’t give it away”. When he returned the dahlia had been given to a nursery and a few years later ‘David Howard’ was out there.

Dahlias are octoploids and they have eight sets of chromosomes, rather than the usual two, so they throw up lots of variations. Other plants have to be more cunning. Wild diascias in South Africa are pollinated by a certain type of bee with long fore legs. Different species growing close together evolve and produce stamens of varying lengths, or in varying positions, so that any pollen deposited sticks to different parts of the bee’s body. This clever system avoids cross pollination. If this particular species of bee is missing, diascia flowers are not pollinated so carry on flowering for much longer, as they do here.

Other plants, like the soapwort and evening primrose, turn their nectar on at teatime as their preferred pollinator is the moth. Plant colour, veining and spotting is there to attract the pollinator and we couldn’t do without them.