It is harvest time. This month, as replete and full of itself as a broker in a wine bar, is the point of all that digging and manure and weeding and turning of compost heaps. The garden is giving it all back with astonishing generosity. There is a very basic practical side to this which is that it is so convenient to go outside at seven o'clock in the evening, without a clue what to have for supper, and simply trawl the vegetable garden like a market. It might be a cliché but hell, it is a fine one to indulge in. Last night was typical. We had little in the cupboard other than the usual mound of half-used packets of pasta. So I took a basket and went outside to gather whatever looked good.

I started with some little French beans, called Twiggy which have been newly introduced this year by Unwins. Each plant was festooned with dozens of bootlace bean pods - the name refers to their slimness (Twiggy, the model, dead skinny, geddit?) rather than their texture. Even a very small garden could easily grow three or four different varieties of French bean if they had a mind to. If you habitually eat from your garden, as I do, it is always astonishing how limited and dull the choice of vegetables in almost every restaurant is. Outside my window we have five types of potato, two varieties of broad bean, three of pea, four of French bean, three of climbing bean, four of lettuce, five of chicory, three of beetroot - you get the idea. Go round any allotment and you will find much the same degree of diversity. The difference in variety is as significant as the difference between wines produced from the same grape in different vineyards.

Then I pulled about a dozen Early Nantes carrots. Carrots are a funny crop. They seem to do nothing much for the first couple of months, especially if you sow them thinly - as you should. But suddenly the top growth takes on lines of frondescence and underground they are hurtling downwards, putting on sleek muscle like an Olympic sprinter. If you pull a carrot from the ground anyone within 10 feet or so will get a strong carroty tang. The intensity of that carrot scent is there in the taste - for about a day. So home-grown carrots are always much sweeter and more delicious than anything that you can buy.

I picked some broad beans choosing pods about eight inches long so that the beans inside would be small and sweet. Broad beans are an essential part of every organic garden if only for the way that they open out and enrich the soil. They have huge roots that go down to a depth of about five feet and these produce nodules that extract nitrogen from the atmosphere and fix it into the soil, which then feeds the subsequent crop - which in our case will be purple sprouting broccoli. Next I pulled a couple of Lobjoit's Cos lettuce - my favourite and at its best at this time of year - and some fresh thyme, marjoram and rosemary for the dressing. We harvested the garlic a week or two ago and it has been drying in the tunnel so that it will store better, but I love fresh garlic and I took a clove to chop and warm up in oil to add after the rest had all cooked.

For pudding I picked some raspberries. Simple as that, with just a sprinkle of brown sugar for crunch and a dribble of cream. All this took 10 minutes at most to get enough to feed five of us with plenty to spare. The carrots were added to the water first, then the French and broad beans, all in with the pasta. I washed and rinsed the lettuce and made a dressing. You have to get your timing right to avoid overcooking either pasta or veg but tennish minutes is about right. Shave some Parmesan over it.

There is a temptation to gloat about the speed of the process, the fact that this incomparably fresh and tasty dish can be knocked up in the time it takes to buy the cheapest, fastest hamburger, but that misses the point. It is slow food. It took at least four months to prepare and in that time there are hours of sowing, pricking out, weeding, thinning and watering. I make no apologies for that. In fact I love the thought that all the slowly accumulated goodness arrives on the dish together. That really is the richness of this time of year - the sense of arrival after a long journey.