For Great Produce, Have a Harvest Agenda
By Kathy Stoner, U. C. Master Gardener
who has filled a couple of shopping bags with 10-pound zucchini and begged
neighbors and friends to take them has experienced that feeling of mystification
and even dread that can occur at harvest time. How do you know when to pick
the stuff, and why did you plant so much?
Planning and a little research are really the keys to a successful
harvest. The first vegetable garden I planted was pretty exciting in the spring
when seeds broke through the soil and nursery seedlings took root and began
to grow. But the garden became overwhelming and confusing when crops seemed
to ripen all at once.
It didn't take me too many seasons to figure out that planting
in waves would give me smaller harvests over a longer time. I learned, for
example, that a radish takes only about 30 days to mature, and it's certainly
best eaten fresh. Instead of planting my whole packet of seeds at once, I
divide it into thirds and plant each third a week or two apart.
This succession planting works well with many crops that are
relatively fast to mature such as green beans, scallions, leaf lettuce and
spinach.
Learning the preferred temperature ranges for my crops also
helped me improve my harvest. I would often read about lettuce and spinach
bolting, with no explanation of what in the world bolting meant.
This phenomenon simply refers to rapid growth induced by hot
weather, which can cause the plant to flower prematurely or develop bitter
flavors. Cool-season crops planted too late will frequently exhibit this behavior.
On the other end of the spectrum, some seeds will simply not sprout and some
plants will languish if the soil is too cold.
So how do we determine harvest time? Much depends on the plant
and the weather. Most vegetable seed packets will indicate the average number
of days until harvest, and some record keeping on your part—which can
be as simple as jotting your planting date on a calendar—will give you
a fairly accurate timeline. Always take into account the weather patterns
and the microclimate of your own garden.
Some veggies taste great even when small. The ubiquitous zucchini
and other summer squashes are notable examples; baby squashes often fetch
a premium in the produce section. Pick them when small and avoid the Giant
Zucchini Syndrome that has plagued all of us from time to time.
Peppers are among the vegetables that you can enjoy when not
fully ripe. Sweet bell peppers start out green, then ripen to red, yellow
or one of the other colors now widely available. Hot peppers are usually allowed
to ripen to red before picking, although jalapeño and serrano chiles
are typically used green.
Bulb onions are a long-term crop, requiring up to six months
to mature. They are ready to harvest when the tops fall over. You can pull
the onions and let them dry aboveground, shading the bulbs with the tops to
prevent sunburn. When the tops and necks are dry, the onions can be stored
in a cool, dark place. The Master Gardener help desk has information on which
onion varieties perform most reliably in our climate.
Cucumbers should be harvested before they get large and seedy, and always
before they begin to turn yellow (lemon cucumbers excepted). Plenty of heat
and consistent watering seem to help control the bitterness that some gardeners
experience with cucumbers.
Corn is ready for harvest 17 to 24 days after the first silks
appear. Husks should be still green, the silks dry-brown and the kernels full
size. When the kernels are punctured, the liquid should be milky white. If
clear, it is too early; if dry, it is too late. For the sweetest flavor, pick
corn just before you are ready to cook it.
Tomatoes are a favorite of the home gardener, for good reason. Once you have
tasted a homegrown tomato, the supermarket variety pales by comparison. An
individual tomato plant, properly cultivated, can produce 10 to 15 pounds
of fruit. Indeterminate varieties continue to set and mature fruit until frost.
Full color development is the usual indicator of ripeness. Keep tomatoes at
cool room temperature, not in the refrigerator, for best flavor.
The Sunset Western Garden Book has excellent information on
many types of vegetable and fruit crops. In addition, Napa County Master Gardeners
can provide regionally specific information to help you succeed with your
garden. Stop by our booth at the Napa, St Helena and Calistoga farmers'
markets, or visit our office in Napa.