Topical Gardening Tips
Question: I love parsley, and I have heard that
it can be sown in fall and grown through winter. Are there any
special things I need to do to make this project successful in my
Zone 6 garden?
Answer:Most gardeners grow parsley
(Petroselinum crispum) as an annual, but it actually is a hardy
biennial. Parsley’s natural life cycle is to germinate in late
summer, persist as a seedling through winter, and then produce
flowers and seeds the following spring. It will follow this natural
rhythm in a garden quite easily if you help the seeds to germinate
promptly — and then provide the plants with protection to buffer
them from the ravages of winter.
Of the two types of parsley most often used — curly parsley and
flat-leafed Italian parsley — curly parsley leaves have a higher
dry-matter content, so they withstand freezing weather a little
better than Italian parsley, which has juicier leaves. All types of
parsley are generally rated as hardy to Zone 5 or 6, but I think
the curled varieties are best for growing from fall to spring.
Late summer to early fall is the ideal time to sow parsley
seeds, which have a well-deserved reputation for germinating
slowly. In more superstitious times, parsley seeds were believed to
travel to hell and back several times before they would sprout.
Virgins were not to sow them lest they risk impregnation by the
devil — this despite the fact that early Christians consecrated
parsley to St. Peter, keeper of heaven’s gates.
A FEW LIGHT FROSTS ARE GOOD FOR PARSLEY, BECAUSE THEY
TRIGGER THE PLANTS TO ALTER THEIR LEAF CHEMISTRY IN PREPARATION FOR
COLDER WEATHER TO COME.
Modern science has found an explanation for parsley seeds’
erratic germination. Parsley seedcoats contain furanocoumarins,
natural herbicides that help parsley claim its space. These
chemicals also inhibit the germination of parsley seeds, but it’s
still an ingen-ious setup. After the furanocoumarins have leached
out and temporarily suppressed the germination of nearby weed
seeds, the parsley seeds finally sprout and start to grow.
Gardeners would prefer that parsley seeds go ahead and sprout,
and one often hears various ways to enhance germination. Last year,
I put three of these methods to the test. After dividing seeds from
a fresh packet into groups of 20, I froze one group in a wet paper
towel, froze another dry, and set another group to soak in
room-temperature water. The next day I planted all the seeds in
adjoining rows, including a fourth row of seeds sown dry from the
packet. The results? Three weeks later, all four groups showed a 50
percent germination rate, with a few more seedlings in the row
planted straight from the packet.
More intensive soaking and rinsing may be a better strategy.
Lots of soaking and rinsing is exactly what seeds get when you
repeatedly water the seeded bed, which keeps the soil cool and
moist (parsley germinates best at 60 to 75 degrees), and gradually
rinses away the furanocoumarins. Once the seedlings are up and
growing, there is nothing more to do beyond thinning them to 8
inches apart, and pulling weeds until freezing weather is
expected.
A few light frosts are good for parsley, because frost triggers
the plants to alter their leaf chemistry in preparation for colder
weather to come. But after the plants have hardened themselves to
cold, it is best to protect them with an appropriate cover from
Zone 7 northward. If you have several plants growing in a row, you
can cover them with a plastic tunnel held aloft with wire hoops,
with the ends left open for ventilation. Or place several stakes
along the outside of both sides of the row and wrap a 12-inch-high
band of clear plastic around the stakes to form an open-topped
opaque cage. Protect individual plants with cloches made from
plastic milk jugs with the bottoms removed. If you cut a slit in
the top of the handle, you can push a stick through the handle and
into the soil, which will help keep the cloches from blowing away.
I protect my winter parsley with milk jugs and surround the
installed cloches with a thick blanket of mulch.
All of these protective devices block cold winds and keep the
plants’ roots on the dry side, which limits the risk of rotting in
cold soil. An insulating blanket of snow is good for parsley, but
in years with little or no snow, you can throw an old blanket over
the cloched plants during periods when temperatures drop into the
single digits.
Remove the plants’ covers as soon as the weather begins to warm
in early spring. Trim off any yellowed leaves, but don’t give up on
plants that appear to be dead. New stems will quickly emerge as
soil temperatures rise, and they will have a remarkably sweet
flavor, a byproduct of their exposure to winter’s cold. They will
bloom in early summer, so plant replacements in spring to make sure
you have plenty of parsley all summer long.
Barbara Pleasant plants parsley twice a year in her North
Carolina garden.
