A hot bed of fruit

I have large hands on the end of rather long arms. But I have always told myself that I am related to a famous England cricketer — the inventor of the googly, no less. But the hands in this picture are the best beloved’s and mine pale into insignificance against his giants. He is fondling a plump Italian aubergine called ‘Bellezza Nera’ from Johnson’s World Kitchen range. It’s described as a “traditional, large oval to round, darkly coloured fruit with excellent flavour and texture” (150 seeds for £1.49 — www.johnsons-seeds.com).

‘Bellezza Nera’ produces wide, ribbed fruits in a pale-purple to aubergine and each large fruit is very glossy. This fruit alone weighed a pound or about 450g. We are also growing ‘Bonica’, ‘Black Enorma’, the compact ‘Fairy Tale’ and ‘Long Purple’. ‘Black Enorma’ has cropped later but seems to be living up to its name. However, ‘Bellezza Nera’ has proved the star.

This sudden success is all very galling for me as I have been trying to grow aubergines for 20 years. I’ve potted them up, placed them in a greenhouse and fed them with tomato feed weekly but the fruits have been sparse and small. But last year I got a new insight when I visited a tender plant nursery and saw a row of aubergines planted straight into the ground in an unheated tunnel. They were tall, vigorous and loaded with fruit due to the humid air and rich soil round their toes.

So this spring a new south-facing hot frame was made (by the B.B.) with wooden sides and sliding glass panels. It looks exactly like a cold frame. But there's a secret ingredient — a large consignment of rotting horse manure for underfloor heating.

This ‘hot bed’ technique is not new. In the mid-19th century most large houses had hot beds or pits and the gardeners were able to produce pineapples, melons and early strawberries. Records show that hot beds were being used in Cordoba c961 and, apparently, the best horses were fed a special diet of barley, beans and alfalfa to promote nitrogen-rich manure (from The History of Kitchen Gardening by Susan Campbell).

Our aubergine seeds were sown on February 29 and placed in a heated propagator on a window sill. They came up on March 9 and were pricked out into individual pots before being planted out on March 28 in snow!

The night-time temperature in the frame never fell below 43ºF (7ºC) and the daytime temperature exceeded 70ºF (20ºC) so the aubergines raced away. By June they were too tall for the 3ft-high frame and had to be pinched out. By July flowers had begun to set, each aubergine taking about four weeks to reach full size.

It has taught me a valuable lesson. Aubergines need to be planted early and grown in the ground. I’m wondering how these beauties would have performed in a normal summer rather than the grey imitation we have endured.