Sustainable Possibilities: crop rotation

Yesterday my son and I harvested basil to make pesto. We were able to quickly harvest about 6 cups worth of basil leaves while barely made a dent in the basil we have growing.

Basil from the garden

This was great news because for the last two years our basil did not do so well. I had been growing basil in the same spot in our garden year after year. The last two years were a far cry from the plentiful basil harvests we had first gotten, and I was wondering if the lack of rotation was contributing to the problem.

So this year, I tried growing basil in several new locations:

I'm growing some basil some in a container on our front porch, I'm growing some interspersed with perennials along the front path, and I'm growing some in a small raised bed where I grew beans and melon last year. The result is a lot of healthy looking basil, and hopefully a lot more pesto to come.

Basil growing in a container on our front porch

There are several great resources that provide guidance on crop rotation (such as these articles from Organic Gardening and Mother Earth News). In general, it's best to avoid growing plants in a location where plants of that family have grown within the last three years. Soil-borne diseases and pests are often specific for one family of plants. If the same family of plants is grown in the same location year after year, the populations of those pathogens and pests may build up in the soil and can lead to poor harvests of those plants. By rotating where plants are grown each year, the pest and pathogen populations stay in check.

Another reason to rotate plants is because different plants have different nutritional needs. Legumes like peas and beans actually add atmospheric nitrogen to the soil thanks to their symbiotic relationship with nitrogen-fixing rhizobia. Other plants, such as leafy and fruiting crops, are heavy feeders and use up a lot of nitrogen. Alternating these types of crops allows them to thrive.

For those with small gardens, it can be hard to figure out how to rotate crops. This is especially the case when there are other constraints, such as making sure taller plants are not shading shorter plants, or making sure climbers such as pole beans are next to a fence. Using containers on my porch allowed me to expand my options (and my garden!) Luckily the local critters (rabbits, woodchucks, deer) did not venture up onto the porch to munch on the basil which was grown without fencing. An additional raised bed also allowed me to expand my crop rotation possibilities. The end result for this year is a healthy basil crop.

Pesto is a huge favorite in my house. Here is the recipe that we use. We used the fresh picked basil and garlic that we harvested last week.

Pasta with pesto

Basil Pesto
6 c basil leaves
1/2 c pine nuts
1/2 c grated parmesan cheese
4 cloves garlic
1/2 c olive oil

Add all ingredients to a food processor and chop!
Toss on whole wheat pasta and serve with fresh cherry tomatoes.

Also harvested from the garden this week: green beans, green beans and more green beans. These green beans are from the black beans that were planted here. The scarlet runner beans that were panted at the same time are flowering but have not produced any beans yet.