Rutabagas have wonderfully aggressive root systems and are capable of growing continuously through long, severe drought. But where I live, the results aren't satisfactory. Here's what happens. If I start rutabagas in early April and space them about 2 to 3 feet apart in rows 4 feet apart, by October they're the size of basketballs and look pretty good; unfortunately, I harvest a hollow shell full of cabbage root maggots. Root maggots are at their peak in early June. That's why I got interested in dry-gardening giant kohlrabi.
In 1991 we had about 2 surprising inches of rain late in June, so as a test I sowed rutabagas on July 1. They germinated without more irrigation, but going into the hot summer as small plants with limited root systems and no irrigation at all they became somewhat stunted. By October 1 the tops were still small and a little gnarly; big roots had not yet formed. Then the rains came and the rutabagas began growing rapidly. By November there was a pretty nice crop of medium-size good-eating roots.
I suspect that farther north, where evaporation is not so severe and midsummer rains are slightly more common, if a little irrigation were used to start rutabagas about July 1, a decent unwatered crop might be had most years. And I am certain that if sown at the normal time (July 15) and grown with minimal irrigation but well spaced out, they'll produce acceptably.
Varieties: Stokes Altasweet (STK, TSC) has the best flavor.
Sorrel
This weed-like, drought-tolerant salad green is little known and underappreciated. In summer the leaves get tough and strong flavored; if other greens are available, sorrel will probably be unpicked. That's ok. During fall, winter, and spring, sorrel's lemony taste and delicate, tender texture balance tougher savoy cabbage and kale and turn those crude vegetables into very acceptable salads. Serious salad-eating families might want the production of 5 to 10 row-feet.
Sowing date: The first year you grow sorrel, sow mid-March to mid-April. The tiny seed must be placed shallowly, and it sprouts much more readily when the soil stays moist. Plant a single furrow centered in a row 4 feet wide.
Spacing: As the seedlings grow, thin gradually. When the leaves are about the size of ordinary spinach, individual plants should be about 6 inches apart.
Irrigation: Not necessary in summer—you won't eat it anyway. If production lags in fall, winter, or spring, side-dress the sorrel patch with a little compost or organic fertilizer.
Maintenance: Sorrel is perennial. If an unusually harsh winter freeze kills off the leaves it will probably come back from root crowns in early spring. You'll welcome it after losing the rest of your winter crops. In spring of the second and succeeding years sorrel will make seed. Seed making saps the plant's energy, and the seeds may naturalize into an unwanted weed around the garden. So, before any seed forms, cut all the leaves and seed stalks close to the ground; use the trimmings as a convenient mulch along the row. If you move the garden or want to relocate the patch, do not start sorrel again from seed. In any season dig up a few plants, divide the root masses, trim off most of the leaves to reduce transplanting shock, and transplant 1 foot apart. Occasional unique plants may be more reluctant to make seed stalks than most others. Since seed stalks produce few edible leaves and the leaves on them are very harsh flavored, making seed is an undesirable trait. So I propagate only seed-shy plants by root cuttings.