Question
I have been an organic gardener for a few years now and I've been wondering about rotating crops (which I do), but I want to know about the TIME factor. They say to rotate crops "every season", but isn't that obvious because every season you cannot plant the same vegetables as the prior season because of the weather. After the summer vegetables, you plant the cool-season ones. So does "season" in this case mean "year"? In other words, you cannot plant tomatoes in the same spot the next YEAR? Nothing I've read clarifies this seemingly simple fact, and I just want to be sure.
Also, because of my limited garden beds space, some years I need to use the same spot for planting the same vegetable as I planted the year before. If I dug out most of the soil in the bed and replaced it with new soil/compost, will this work? It's not as laborious as it seems as it is not such a huge bed, maybe 5 ft by 3 feet at most, and I make my own compost so I have plenty. Thank you for any advice you can give me.

Answer
Dear Suzie:

Crop rotation can reduce insect and disease damage since pests and disease-causing organisms tend to increase when their host is continuously grown in the same location. For crop rotation to be effective, you need to know the genetic relationship between common garden crops. For example, you should not follow tomatoes with peppers since these plants are closely related and many of the same diseases and insects attack both. Crop rotation is especially effective with soil home diseases. Rotation periods are three to five years and may be difficult in a small garden.

You didn't indicate if you use the raised bed method of gardening, if you do then all the better for what I consider an optimum plan for your situation.  I recommend that you create a second bed of similar size and alternate crops between the two beds every year.  I would also continue to replace the soil in each bed on a biennial basis.  Otherwise, your present approach of replacing the soil in the single bed is an excellent method for prevening possible exposure to soil borne diseases when crop rotation is not practical as in your particular case.

Keep up your dedication to organic gardening!!

Regards,

Mack Jean
AllExperts
Master Gardener
Tennessee