Part 4: how many beds?
How many garden beds do I need/want?
Before you get to building you need to figure out the size and number of beds you want to make. For me the most important consideration is having enough garden beds to make sure you can rotate your crops. This is the most important thing you can do for pest control and nutrient retention which will greatly affect the general health of your soil and plants. The rotational principles are simple: never plant the same species of vegetable in the same garden bed/plot for 3 years. That is, the same family/species of plant should only be in one garden bed every third year. So I would argue that you want at least 3 garden beds (even if you choose to make 3 smaller beds instead of one large bed). This way you can plant the things you like every year. So if you want tomatoes every year then you can plant them in plot A on year 1, plot B on year 2, and plot C on year 3. You’ll thus avoid getting nematodes that will make growing tomatoes impossible. Four beds are even better and a nice square plot with 4 4*4 beds will look nifty as a starter area. Even better would be 4 8*4 beds.
Remember too that the rotation applies to entire families of plants. Tomatoes, peppers, and regular potatoes are all nightshades. So if you only have 3 plots, you can’t rotate those three crops between them because you’ll risk attracting pests that attack all nightshades. Radish, Turnips, and Kale are all brassicas so you can’t rotate those through your 3 beds on a yearly cycle. Cucumbers and squashes are cucurbits and can’t be in the same plot within 3 years of each other.
If you only have one bed or two beds you can get creative in your plantings. In Virginia if you do this right you can get three crops in a bed each year; this is intensive succession planting and it works well. You just have to remember the families of plants. For example, if I had one garden bed I would do this on a 3 year rotation:
Year 1: Spring carrots (harvest), then plant summer radishes (harvest), then plant fall carrots (harvest).
Year 2: Spring beets (harvest), then plant summer cucumbers (harvest), then plant fall spinach (harvest)
Year 3: Spring snap peas (harvest), then plant tomatoes (harvest), then plant fall/winter lettuce (harvest)
What you should not do is keep planting the same family of plants in the same spot and then be surprised that you have bugs and diseases. Some may then resort to spraying pesticides, fungicides, or other chemicals. Don’t do this even if it’s a certified organic treatment. Just grow what you can with the resources that are available to you; you can support your local farmer by buying tomatoes on the years that you can’t grow your own (then pair them with the delicious Suyo Long cucumbers you grew yourself). As we talk more about pests later I do not think there is a good reason for a home gardener on this scale to use sprays/treatments even if they are natural and certified organic. We’ll keep our soil and plants healthy to deter pests themselves (they have immune systems) and we’ll use physical barriers to prevent pest problems before they start.
You can find lots of great resources online to describe plant types but here are some of the basics:
Brassicas: all types of cabbages, rashes, broccoli, cauliflower, turnips, kale, mustard greens
Cucurbits: cucumbers and squashes (winter and summer squash and pumpkins etc.), melons
Solanaceae (nightshades): potatoes, tomatoes, peppers, eggplant
Apiaceae or Umbelliferae: carrots
Chenopodiaceae: beets, spinach
Convolvulacea: sweet potato
Alliaceae: onions
Asteraceae/compositae: lettuces