My time at The Lost Gardens of Heligan began in the autumn of 1993 when the restoration was in its infancy. I had just come back from a lengthy trip to India where I was helping on another restoration project, this time a redundant coffee estate which had fallen badly into disrepair.
The garden at Heligan was also in a very poor condition but plenty of work had been done by the time I arrived and gardening, rather than slashing and burning, was all set to get under way.
The vegetable garden had been cleared of all the undergrowth that had engulfed it over some 70 years of abandonment. Following that a great deal of it had been sown with potatoes, ostensibly to clear the ground. An interesting concept this and one that I have never quite been the right side of. The process assumes that the ground has already been cleared of perennial weeds because the only weeds that ridging up will clear are annual ones, perennials such as docks and or nettles will only re-root and possible multiply if chopped up.
Once the potatoes were lifted that autumn the process of planning the gardening came into view. Today the vegetable garden is worked on a six course rotation but back then we started with only four courses. Plot One was potatoes with winter brassicas in the same year, Plot Two was roots such as carrots and parsnips, Plot Three was legumes i.e. peas and beans and Plot Four was miscellaneous including summer brassicas and onions. All the crops moved on one plot each year roots following on from potatoes and so on.
The purpose of rotation is twofold - to keep plants in the same family together and therefore break the cycle of soil borne pests and diseases and to build soil fertility adding the correct nutrition for each crop at the right time. The practice has been in use since agriculture began and it works. So for example lets take the profile of Plot One over four years. It has potatoes in the first year and these are gross feeders and require liberal dosings of well rotted manure. As such the ground is dug over and the organic matter is added. After the potatoes are harvested the ground is raked over and the winter brassicas are planted. Whilst the potatoes have used up most of the nitrogen supplied by the organic matter there will be just enough left for the cabbages and kales which follow on. When planting these it is important to remember that the ground should be firm, especially for cauliflowers and brussels sprouts. The next year is the turn of the carrots and parsnips. By the time the brassicas come out there is not too much nitrogen left in the soil which is perfect for these straight growing root crops. What they like best of all is a sandy soil without large stones.
In the third year the plot has its nitrogen replaced by the leguminous crops in the shape of peas and beans. To me it has always been one of the great miracles of nature how a plant can take atmospheric nitrogen, store it in bacteria which is held ion nodules on the plants roots and release it to nourish itself and other plants around it. Astonishing but that is what peas and beans do and when you dig up a broad bean or runner bean plant at the end of the season you will see the funny pink wart like growths in which the nitrogen is found.
The fourth in line are the miscellaneous crops that dont fit in such as spinaches and chards, onions, summer brassicas and oddities such as celery and celeriac. Today at Heligan there are six courses to the rotation and the plot would get onions after the legumes and then be trench dug with manure added for pumpkins and squashes, the miscellaneous following these.
So the rotational aspect of managing the vegetable garden at Heligan continues to this day and the results are a testament to the old fashioned system of growing in rotation. The garden is almost entirely organic, apart from one systemic fungicide used to counteract potato blight on the main crop potatoes and there are no herbicides or pesticides used at all.
It is the same with the flower gardens and the borders. They too are managed organically with the emphasis on soil fertility and correct nutrition. For annual cut flowers too much nitrogen will lead to lots of lush leaf growth and not too much in the way of flower but for perennial plants which are bigger and older there is definitely a considerable nutritional requirement and the use of winter and spring mulches in the form of compost is widespread.