The basic rule for deciding which edible crops to plant is to grow what you like to eat and what your growing conditions allow. You have control of the soil, so light is the most limiting factor. Most vegetables require a minimum of six hours of direct sunlight a day. Leafy vegetables (lettuce, spinach, chard and various other greens) can tolerate more shade than root crops (beets, carrots, potatoes). Fruiting crops (tomatoes, peppers) will not thrive at all in a shady spot. It is important to grow varieties adapted to our cool, cloudy climate, especially those of heat-loving crops such as tomatoes and peppers.
To get the most food out of a small space, grow crops that can be harvested continually over a long season. Hardy, leafy plants, such as chard, spinach and kale can be harvested this way. You can also prolong the harvest by sowing leaf crops very thickly and thinning them for salad greens. Thinning allows the remaining plants room to grow, and they can be thinned again each time they get crowded. Grow green onions, leeks, beets and lettuce this way.
Many vegetables can be seeded directly into adequately-sized containers. Follow the seed packet instructions for planting depth. Yields of all crops will be increased by closer spacing, up to a point. A good rule to follow is to grow plants at the distance recommended for space “in rows″ on seed packets and ignore the recommendation for space “between rows.” For example, a beet seed packet says to space plants 3 to 4 inches apart in rows 12 inches apart. You can grow them spaced 3 to 4 inches apart in both directions by offsetting the seeds. Generally, spacing plants closer will result in a higher total harvest of slightly smaller individual plants. This concept may be economically applied to crops like cabbage, which may be grown very close together (12 inches) to yield more reasonably sized heads than the normal.
Starting plants inside early and moving them outside as weather permits is a good way to get early crops of many plants. Plants must be conditioned (hardened) to withstand the cold and wind they will encounter outside or they will suffer permanent damage from the change. Hardening is done by putting the plants out in a protected area and bringing them back inside at night for several days. Withholding fertilizer and water before putting them outside can also help harden them.