USDA Climate Zones and Other Gardening Tips

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USDA climate zones stretch in bands across the country, each encompassing distinct seasonal growing conditions.

The shimmering heat of summer lies heavy upon the land. As
parading thunderheads pile high in the sky, wait for the
first fat drops of precious rain to release the earth’s
rich fragrance. Later–after the soil’s thirst is slaked and
the storm rumbles away–feast on fresh corn, beans, cabbage,
and tomatoes, and give thanks for the season and for
the goodness of the garden.  

Summer Gardening

We try on
occasion to bring you detailed gardening suggestions,
tailored to the USDA climate zones.
Of course, regional variations exist just about everywhere,
and advice that’s suitable for a general location may have
to be modified to suit any particular site. Still,
you should find our suggestions pretty close to the mark
for your region. Just add your knowledge of local
conditions, and get gardening!    


Even in
always chilly Zone 3 (where frost can come in early
September and the winter temperatures sometimes drop
below -30°F), you can plant a second crop of
heading lettuce or endive as late as mid-July. Turnips, peas, and kohlrabi can also be seeded up to the
15th of the month. Other greens–such as leaf lettuce,
spinach, and mustard–can be sown all month long.
Radishes will crop if planted in July or the first half of
August, and early turnips (such as Tokyo Cross) should
mature if they’re sown before August 10th.


folks up in cool Zone 4, where frosts often occur around the
first of October, can plant bush beans, Chinese cabbage,
beets, carrots, and Swiss chard through the first week of
July. Transplant your all cauliflower seedlings
before mid-month, and sow kale and kohlrabi seeds by then,
too.You can start endive, lettuce (both heading and
leaf varieties), mustard, peas, radishes, spinach, and
turnips almost anytime during July. August, however, offers
less opportunity: Spinach can be sown until the 15th, and
some of the minor greens (corn salad and cress) will beat the
frost even if planted later still.


Gardeners in Zone 5 have a relatively wide range of choices
available to them. Up to mid-July, brussels sprouts and
broccoli seedlings can still be set out, as can cabbage
transplants. The 15th of July is the last day for planting
seeds of okra, rutabaga (so sweet and mellow on a winter’s
evening!), summer squash, and heat-loving New Zealand
spinach. You can normally plant bush beans, beets,
cauliflower seedlings, carrots, and Swiss chard through the
third week in July. Chinese cabbage, kale,
turnips, parsley (mulch it well and it’ll even winter
over), and kohlrabi can be started anytime this month.

August, you can plant leaf lettuce, endive, and mustard
before the 15th. Spinach, radishes, and turnips
can probably be put in all month long. Early in August,
tip-prune your melons and winter squash. All the energy
that would have gone into setting flowers will be thrown
into ripening the fruit that’s already on the vine.


Since the first frost in Zone 6 occurs about October 20,
you folks can still do a good deal of planting. During the
first two weeks of July, for example, it’s safe to sow bush
beans, corn, cukes, melons, summer squash, and rutabaga.
Pepper transplants (especially varieties–like Canape
and New Ace–that set fruit well in cooler weather)
can also be set out till mid-July, as can potatoes. Plant
brussels sprouts seedlings, beets, broccoli transplants,
Chinese cabbage, carrots, cauliflower (transplants, of
course), Swiss chard, collards, kale, kohlrabi, leaf
lettuce, New Zealand spinach, and turnips anytime
in the month of July.

Zone 6 gardeners can keep busy in
August, too. Until the end of the second week, Chinese
cabbage, kale, kohlrabi, parsley, and turnips can be sown.
Many salad makings (lettuce, endive, mustard, and radishes)
can be planted all month, while the fall spinach crop
should probably go in around the 15th. And don’t forget to
sow a cover crop of winter rye in any area of the garden
that’s finished producing vegetables.


If you live in temperate Zone 7, you can choose among a
wide variety of succession crops. With the first
frost due around November 1, there’s time for many foods to
reach maturity. You can still plant limas or bush beans,
broccoli or brussels sprouts transplants, carrots, Swiss
chard, chicory, early corn, cucumbers, black-eyed peas, New
Zealand spinach, and summer squash anytime in July. During
the first half of the month, sow melons, soybeans, winter squash, and transplant peppers.

Then, from
July 15 to mid-August, you can set out cauliflower seedlings
and plant potatoes. During all of August you can
sow Chinese cabbage, beets, Swiss chard, kale, kohlrabi
(generally the Purple Vienna variety–or the Grand
Duke hybrid–will be best for fall), lettuce, parsley,
peas, and turnips. Mustard and radishes will get a good
start in the cooler weather of late August.


In southerly Zone 8 (where frost often arrives in
mid-November), July is too blamed hot to plant some
vegetables … but heat-loving lima and bush beans, corn,
cukes, black-eyed peas, pepper seedlings, and soybeans will
flourish if planted at any time of the month. You lucky
folks can set out tomato and eggplant seedlings until
mid-July, and plant seeds of winter squash during the same
period. The second half of the month provides prime
opportunities to make fall-ripening plantings of
watermelons, muskmelons, and rutabagas.

August, being a
little cooler, is actually a better month for succession
planting in Zone 8 than is July, and is a good time to sow
bush beans, beets, broccoli, brussels sprouts, carrots,
Swiss chard, endive, garlic (to be harvested next
year), kale, and shallots (they’ll winter over, too). You
can also set out cauliflower transplants and start more
potatoes. Things should cool down enough by the 15th to let
you safely sow Chinese cabbage, collards, kohlrabi,
lettuce, mustard, and tangy sorrel.


In the balmy reaches of Zone 9, where frost holds off until
December, both July and August are ideal months for
transplanting eggplant, peppers, and tomatoes, and July
is a good time to sow Swiss chard, cukes, okra (mmm …
gumbo!), black-eyed peas, soybeans, and summer squash.
Winter squash can be planted between mid-July and mid-August, while limas, bush beans, broccoli, brussels sprouts,
and potatoes can be sown at any time in August.


Folks in the heart of the sunbelt–Zone 10, where
frost doesn’t arrive till mid-December (if it comes at
all!)–can transplant peppers, eggplants, and tomatoes
in July and August. Both months are fine for putting in
Swiss chard, black-eyed peas, and summer squash too,
but long season soybeans should be planted in July. And
August is best for sowing brussels sprouts, potatoes,
broccoli, and okra.

Finally, southern gardeners should know
about a beautiful new book by Richard Ray and Lance Walheim, Citrus: How to Select, Grow and Enjoy. The
fine large-format paperback is crammed with magnificent
color photographs and detailed growing advice on over 100
varieties of familiar and unfamiliar citrus
fruits, including some (like the pummelo, calamondin,
and citrangequat) that most folks have never heard

Ofelix Salix: Rooting Hormone Catalyst

The Avant Gardener, that gold mine of horticultural
information (it’s available, at a cost of $15 for a year
of twice-monthly issues, from Horticultural Data
… and well worth the price), recently reported on the
discovery of a potent root-promoting compound that comes
from willow tree (genus Salix) cuttings. The substance,
which is not a rooting hormone but greatly increases the
effects of such products, is said to produce dramatic
results. In one test, for instance, hard-to-start yellow
birch cuttings failed completely when rooting was
attempted with a standard 0.3% hormone treatment, but
achieved 100% success when the willow extract was added
to the hormone.