THE GARDENING YEAR
“I’m a year-round garden, yes you
know it’s true.” The Pacific Northwest’s mild climate is conducive to
year-round food growing, as celebrated in the Beetless’ TWELVE MONTHS A YEAR.
Not every crop grows year-round, of course. Some grow only in the warmer or cooler
parts of the year. Some require protection of a greenhouse for some or all of
their lives; others survive outside even during the coldest winters.
But before we dig too deeply into
the particulars, we need to step back and ask a few questions:
1. What conditions change throughout
the year? Why, and how, does this make a difference to crops?
2. Don’t these crops just grow
naturally here anyway? Why do we need to concern ourselves with “timing” and
“seasons”? Where are these crops from, anyway?
To address question #1, anyone with
a familiarity with seasonal cycles will have noticed that several things change
throughout the year:
a. Sun angle and day length. Many
vegetable crops thrive on sunlight, and grow best when the sun is strongest and
shines for a long time every day. (When it’s highest in the sky at summer
solstice on June 21, it is filtered by the least amount of atmosphere; this is
also the longest day of the year.) On the other hand, some crops prefer at least
partial shade--less intense sunlight, and less of it. Hours of sunlight and
darkness also trigger predictable responses in the internal biological clocks
of “photoperiodic” plants (like onions, garlic, and leeks). These plants are
stimulated to flower, or bulb, or die back when the light/dark balance reaches
a specific point.
b. Temperature. Soil temperature,
average air temperature, and also maximum and minimum air temperatures all have
powerful effects on plant life cycles, and these fluctuate throughout the year
as well. They generally reflect a lag time of a couple months from the sun
angle/day length cycles; the warmest growing months are usually July and
August. Soil temperature is a crucial factor in plant growth, as is air
temperature. Maximum and minimum temperatures are both limiting factors in the
growth of certain crops. Above certain temperatures, some seeds will not
germinate, and some plants will become weakened, diseased, pest-prone, and/or
dead. Below certain temperatures, other seeds will not germinate, and some
plants will be killed by frost.
Not all plants freeze at precisely 32
degrees Fahrenheit—in fact, few do. Sugars in the cells of frost-hardy plants
act as antifreeze, and sclerophyll tissue (which makes leaves leathery) offer
further protection, lowering the freezing temperature. On the other hand, many
plants, including the “American” crops (tomatoes, potatoes, peppers, corn,
beans, squash) and also cucumbers, eggplants, basil, and others, can die at 37
or 38 degrees Fahrenheit if the night sky is clear. This is called a “radiation
frost,” and is lamented in the Beetless’ I'VE JUST SEEN A FROST. When staring into the intense cold of outer space, with no
cloud cover, plants—and water, for that matter—will freeze even when air
temperatures are several degrees above freezing. (This principle has also been
used to make ice in the desert.) Protective measures against radiation frosts
include covering crops with spun polyester, plastic sheeting, or bed sheets—or,
more commonly, turning a sprinkler on before the temperature dips to 38 F. The
water freezes on the surface of the leaves, offering an insulating layer which
keeps the leaf temperature itself from dipping below 32 F. (Because of the
sugars in the leaves, even these frost-tender plants do not freeze at that
temperature.)
c. Rainfall and moisture. Most of
our rain falls during the fall, winter, and spring; very little falls in the
summer. Those crops which need summertime moisture, or crops growing in a
greenhouse where natural rainfall does not reach the soil, need supplemental
irrigation.
d. Pests and diseases. Populations
of “pest” species also fluctuate throughout the year, as a response to the
above three factors and their impacts on the rest of the ecosystem. Some pests
thrive in the damp, and don’t mind some cold; others are present only during
the hot times of year. Each organism has its own life cycles, linked not only
to the seasons but to the life cycles of other organisms, including garden
plants. Pests can be vectors of diseases, which also have their preferred times
and conditions to strike. Even where the first three factors above are not in
themselves direct limiting factors to the growth of certain crops, the pests
and diseases associated with them may counterindicate growing those crops
during particular seasons.
It’s
important to remember that some plants are annuals, some are biennials, and
some are perennials. Annuals go from seed to seed in one year—they complete
their growth and reproductive cycles in the same year in which they are sown.
Biennials spend their first year growing vegetatively, and then flower and make
seed in the second year. And perennials continue to live more than two years,
although they may flower, fruit, and make seed each year while doing so.
So this
brings us to question #2 above: Why do we even need to worry about seasonal
cycles? Aren’t these plants natural here? Can’t they take care of themselves
without our keeping track of their schedules?
The answer, put most simply, is no.
Almost none of the garden plants we grow are native to this area. In fact,
almost none of them are native to the North American continent. As GOOD DAY SUNCHOKES explains, just four commonly cultivated world crops come from North America: sunflower, cranberry, blueberry,
and sunchokes (Jerusalem artichokes). (More recent information reveals
that a few varieties of squash also originate in eastern North America.) The rest come from elsewhere.
Ironically,
the crops we call “American” crops—including beans, corn, squash, tomatoes,
potatoes, and peppers—are among the least suited to our climate, since (except for a few varieties of squash) they originate in
the subtropics of Central and South America. They are killed by frost, and require warmth to
grow well. Other warm- and hot-weather crops originating in subtropical regions
include cucumber, basil, eggplant, okra, and melons; the last three, in
particular, tend to be even more marginal in our area. Season-extension methods
(starting the seeds in greenhouses in late winter or early spring) are required
to induce tomatoes, peppers, eggplants, and okra to produce significant amounts
of mature fruit here. Beans, corn, squash, cucumber, basil, and melons are
usually sown after the danger of frost has passed, and, like the others, are
killed by the first frost in the fall (or in the late summer, when it sometimes
arrives). (See I'VE JUST SEEN A FROST.)
Crops originating in temperate
regions of Europe and Asia—sometimes referred to as
“Mediterranean” crops—are actually much more compatible with our climate than
are the “American” crops. Most are at least somewhat frost-hardy, and many can
live through our mild winters outside without suffering any cold damage. Even
more can survive our winters in a greenhouse. For some of these crops, summer
is actually the most stressful time—cabbage family members (celebrated in GREENS THAT ARE MUSTARDS) and many salad greens actually prefer cooler
temperatures, as do peas, favas, garlic and other onion family members, and similar
crops. Wild crops are also seasonal, with fruit ripening throughout the warm
periods of the year but fungi (see I'M A SHROOMER) thriving in the damp of fall
and spring.
Garden activities are also affected heavily
by the cycle of the seasons. Some are determined by crop cycles. For example,
seed collecting (see ALL YOUR SEEDS ARE LOVE and YOU WON'T SEED ME) obviously
needs to happen when seeds are ready to collect. Pruning of fruit trees and
other fruit-bearing crops either within the garden or in separate orchards can
be done at different times depending on the desired effect—stimulating fruit
production or influencing vegetative growth (see MISTER PRUNE-RIGHT). Other
activities are determined simply by weather conditions. High soil moisture
levels during the rainy season often prevent cultivation of garden beds;
working wet clay soils can destroy soil structure and create lasting compaction
(see SHE DUG YOU). In summer, moisture levels can be controlled through
irrigation decisions, allowing much greater flexibility. This flexibility is
available year-round in protected greenhouses and cloches, except when soil
saturation is so great that it waterlogs even covered garden beds.
Many sources offer information about
appropriate sowing dates for various crops. Here are some general guidelines
for our area, with additional notes reflecting our experiences here at Lost Valley. These guidelines will be
elaborated further elsewhere in this guide:
January-March:
Sow leeks, onions in flats in greenhouse (we often wait until March, but they
can be started earlier).
January-continuous
throughout year: Sow lettuce, other salad crops in flats in greenhouse
(midwinter germination and growth can be slow or nonexistent depending on
temperature, so in reality we usually skip the coldest midwinter months).
February-May:
Sow peas directly in the ground—in greenhouse beds, if early, and/or in
outside beds.
February-March:
Sow parsley, celery (we usually wait until March for reasons of temperature;
early sowing is essential, because germination takes three weeks and growth is
slow).
March-August:
Sow root crops directly in ground, in greenhouse or outside (check suggestions
for individual root crops; radishes can be sown even later).
March-September:
Sow brassicas and other cooking greens in flats (in greenhouse, early, or
outside if later) and in ground.
March-July:
Sow flowers (depending on variety).
March-April:
Sow tomatoes, peppers in flats in greenhouse (early sowing is recommended).
April-June:
Plant potatoes in ground (allow three months to mature; vegetation is frozen
back by frost, but will resprout if growing conditions are still favorable).
mid-May-mid-June:
Sow squash, melons, cucumbers in pots or directly in ground; sow basil in flats;
sow corn directly in ground.
mid-May-June:
Sow beans directly in ground, sunflowers in flats or in ground, buckwheat
(throughout summer) directly in ground.
June-August:
Sow fall and winter brassicas and other greens in flats or directly in ground.
August-November:
Sow winter cover crops (such as clovers, field peas, vetch, rye) directly in
ground.
September-October:
Plant garlic directly in the ground.
October: Plant
favas directly in the ground.
October-November:
Sow peas directly in the ground.
In summary, our temperate climate
offers the opportunity for great diversity and abundance from our gardens.
While we can’t grow any crop imaginable (see OH! BARLEY), we can grow a healthy
variety of fresh produce all year round, which can be supplemented by stored
and preserved seasonal produce to create a well-rounded, tasty bioregional diet
(see SALT AND PEPPER'S ONLY FOR WHEN
VEGETABLES ARE BLAND). Our mild winters
and summers mean that a motivated gardener can almost always stay busy with
outdoor and garden-related activities if desired, reducing the seduction of the
“old 9 to 5” even further (see WORKDAY).
Other Beetless tunes not mentioned
above that deal with topics at least tangentially related to this chapter are
referenced in the “Beetless’ Bootleg” APPENDIX—their lyrics have been lost,
but the notations do offer some information. These include A DAY IN THE LEAF
(which celebrates photosynthesis), FOR NO SUN (which considers various possible
culprits for the death of a plant, including unfavorable weather and lack of
sun), HAPPINESS IS THE WARM SUN (especially for “American” crops), HEY BULLFROG
(luckily, these nonnative invaders need year-round bodies of water to survive
and reproduce, and our pond dries up), HOE SNAP PEAS, HOE FAVAS (more on some
cool-weather crops), MELON SAYS PICK ME (a rare late-summer delight here), SAVOY
CABBAGE (much more compatible with our climate), and SLOPE DOWN (which deals
with the process of garden siting, in which it is essential to consider sun
angle and other factors which change throughout the year).
(forward to Pt. 2) (back to Gardening Guide index)