Establishing the Fall and Winter Garden

West of the Cascades, germinating fall and winter crops in the heat
of summer is always difficult. Even when the entire garden is well
watered, midsummer sowings require daily attention and frequent
sprinkling; however, once they have germinated, keeping little
seedlings growing in an irrigated garden usually requires no more
water than the rest of the garden gets. But once hot weather comes,
establishing small seeds in the dry garden seems next to impossible
without regular watering. Should a lucky, perfectly timed, and
unusually heavy summer rainfall sprout your seeds, they still would
not grow well because the next few inches of soil would at best be
only slightly moist.

A related problem many backyard gardeners have with establishing the
winter and overwintered garden is finding enough space for both the
summer and winter crops. The nursery bed solves both these problems.
Instead of trying to irrigate the entire area that will eventually
be occupied by a winter or overwintered crop at maturity, the
seedlings are first grown in irrigated nurseries for transplanting
in autumn after the rains come back. Were I desperately short of
water I'd locate my nursery where it got only morning sun and sow a
week or 10 days earlier to compensate for the slower growth.

Vegetables to Start in a Nursery Bed

Variety Sowing date Transplanting date
Fall/winter lettuce mid-August early October
Leeks early April July
Overwintered onions early-mid August December/January
Spring cabbage mid-late August November/December
Spring cauliflower mid-August October/November 1st
Winter scallions mid-July mid-October

Seedlings in pots and trays are hard to keep moist and require daily
tending. Fortunately, growing transplants in little pots is not
necessary because in autumn, when they'll be set out, humidity is
high, temperatures are cool, the sun is weak, and transpiration
losses are minimal, so seedling transplants will tolerate
considerable root loss. My nursery is sown in rows about 8 inches
apart across a raised bed and thinned gradually to prevent crowding,
because crowded seedlings are hard to dig out without damage. When
the prediction of a few days of cloudy weather encourages
transplanting, the seedlings are lifted with a large, sharp knife.
If the fall rains are late and/or the crowded seedlings are getting
leggy, a relatively small amount of irrigation will moisten the
planting areas. Another light watering at transplanting time will
almost certainly establish the seedlings quite successfully. And,
finding room for these crops ceases to be a problem because fall
transplants can be set out as a succession crop following hot
weather vegetables such as squash, melons, cucumbers, tomatoes,
potatoes, and beans.

Vegetables that must be heavily irrigated
(These crops are not suitable for dry gardens.)

Bulb Onions (for fall harvest)
Celeriac
Celery
Chinese cabbage
Lettuce (summer and fall)
Radishes (summer and fall)
Scallions (for summer harvest)
Spinach (summer)