The first 2010 seed catalogue arrived today. Wowie! Many pages to pore over, and lots of planning to do.
Now I know that some of you reading this won't have much of an idea about what goes into planning a vegetable garden, so I'm going to explain as much as I know so far. Please believe me: I'm not making any of this up.
The first thing is to make a list of what you might like to grow. This list, I have learned, should more or less correspond to what you might like to eat. I learned this the hard way, when I didn't acknowledge the fact that I really don't like kale only after I had a bed full of it ready to harvest. When you make the list of what to grow, it's important to recognize that your space is probably limited, and you won't have room for everything. So, as well as thinking of what you might like to eat, think of things that are hard to get in the grocery store (like purple potatoes), or are expensive to buy (like basil). Some things, like onions, are dead cheap to buy, but the homegrown ones are so much better you should go ahead and plant some anyway. Also, especially for new gardeners like me, it's probably a good idea to stick to things that are easier to grow.
The next thing is to look at the space you have and see what you can fit in. This is more complicated than you think, because some crops (like garlic) will be harvested by July, leaving an empty bed ready for something else. You may be able to get three different crops from a single bed: early radishes and green onions, followed by beans, followed by Swiss Chard or (yuck) kale to harvest through the winter. This is especially true if you are starting seeds in soil blocks and then transplanting them when they are partly grown. So you need more than a plan with a space for each bed - you need a plan that takes into account time, too.
Which leads to the issue of crop rotations. It's important not to plant the same crop in the same bed two years running, because it gives pests and diseases a better chance to make a permanent home there. Also, some crops use lots of the nutrients in the soil, so you shouldn't plan two such crops in a row. So you can't really plan a garden for a year - you should really plan it at least 3 years ahead, to make sure you've accounted for all the crop rotations you'll need to do.
If you've followed all that, you'll have a plan for what vegetables are going to be planted in what beds when, for the next few years. The next thing is to choose the varieties - that's where the seed catalogues come in. For example, suppose you're thinking of carrots. There are lots of options, depending on what you want. Early carrots or late carrots? Carrots you plan to eat right away or store for future use? Orange carrots, red carrots, purple carrots or yellow carrots? Long, skinny carrots or short, fat carrots? Do you need a variety that is resistant to any particular disease or pest that is common in your area? Do you want a hybrid (often bred for resistance) or an open-pollinated variety (which means you can collect the seeds for planting the following year)? Although the choices will seem endless (especially if, like me, you are cross-referencing 3 or 4 different catalogues) you should probably stick to 2 varieties - more is just plain silly.
When all this is done you'll have a plan for your garden, and a list of what seeds to order. The last ingredient is a calendar of planting dates. After all, it would be a shame to realize in June that your peas should have been planted in April.
Your calendar of planting dates needs to take into account a few things. First, know the planting zone in which you are located. Gardening in Victoria is very different from gardening in Thunder Bay. Second, read the information given in the seed catalogues or any reference books you have, in order to get a rough idea of which weeks or months you should be planting in. Third, think about whether you want all your beans, for example, ready at the same time - say, if you wanted to pickle them. If so, plant them all at once. If not, be sure to stagger the planting across several weeks. Cross-reference that with all your other information and you'll have a good idea of what to plant when.
If you're really keen you can also consult a calendar to see when the moon is waxing and when it is waning. According to biodynamic farming principles, it's better to plant vegetables in which the desirable part is below the ground (like potatoes or radishes) when the moon is waning, and vegetables whose upper part you want to eat (like salad greens or peas) when the moon is waxing. (This is the time when I need to remind you I'm not making any of this up...)
Call me obsessive, call me anally-retentive. But I have a week-by-week calendar for what gets planted when that takes me from late January (when onions and leeks get started in the greenhouse) to mid-September when the last radishes and lettuce for eating through the winter are planted. I am a planner, and I am proud!