To
wrap up the first year of gardening in the greenroom – March 2013
to the present, May 2014 – I wanted to write up our greenhouse
growing successes and failures. This first year was highly
experimental, especially growing through what I’m calling the
“heart of winter,” and I think we learned some very interesting
things that will help guide next year’s plantings, both the timing
and the varieties. I’m more interested in “heart of winter”
greenhouse gardening than mere summer-season extension gardening
because this is all the fresh garden produce we get during the middle
of winter. Shoulder season (spring/fall) crops and using the
greenhouse to extend the summer season will be discussed in other
posts; this is all about what we tried, succeeded, and failed to grow
during the coldest and darkest months of the year.
Attempted
crops for the heart of winter greenhouse season included basil,
beets, Brussels sprouts, chard, cucumber, kale, lettuce, okra, peas,
peppers, radish, tomato, and a few herbs. The short version: we’re
going to become radish farmers! Much, much more detail is given
below.
“Heart
of Winter” Summary:
Successes:
Beets, Chard,
Coriander, Kale, Lettuce, Radish, Tomato
Semi-successes:
Basil, Broccoli,
Leeks, Hot Peppers
Failures:
Brussels
Sprouts, Cucumber, Okra, Parsley, Peas, Thyme
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I keep track of planting dates, harvest dates, quantity and quality of produce, and we also concurrently have some temperatures sensors outside and inside the greenhouse. Still, this is very much a crapshoot at this point as we figure out what we can grow in the greenhouse without supplemental lighting and only minor supplemental heat (to keep it just above freezing).
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| Frosty greenroom on a cold winter morning. |
There wasn’t a real rhyme or reason to the timing of planting during this first, experimental winter greenhouse season; due to misdirected attention (to the summer garden), I missed the autumn August/September planting opportunity while the days were still long, so the first set of tests I performed were an October planting for these crops that I’m calling “Heart of Winter” – that is, plants that would have to withstand short days (no artificial light) and air temps down to almost freezing in the greenhouse. To make matters worse, during sunny days (most winter days are sunny here in New Mexico) the greenhouse gets anywhere from 90 to over 100 degrees depending on whether we open the doors to the house. (The design and some basic temperature data from the greenhouse are discussed here.) Let’s say the “heart of winter” plantings run from October to mid-January, as plantings in February begin to take advantage of the lengthening days. Let’s call those the Spring season, because that’s when they’ll be harvested (keeping in mind that this is all still referring to greenhouse growing, not outdoors, but there are seasons in the greenhouse too).
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| Greenroom planting categories. |
Because
we’re still just beginning to understand the success of the
“Spring” plantings right about now, I’ll cover those in a later
post. The summer greenhouse season isn’t all that important because
we’re growing so much great stuff outside. Plus, our greenhouse turns into a shady porch and hangout spot in the
summer with a 50% shade cloth, and we remove the racks that we add in
the winter to increase growing space. The fall greenhouse season has
not been fully explored. The greenhouse starts for the summer outdoor garden I will
cover somewhere separately, because these will be transplanted
outside the greenhouse after the last frost.
Here’s a chart of the first year of greenhouse operation, beginning in March 2013 up to April 2014. Open circles are the plant date, and I’ve shaded the regions of the calendar by the planting seasons above. This diagram shows how long it takes various plants to grow to maturity and harvestability. This diagram only shows the true successes, not the failures or the hot peppers, which only recently turned from a failure to a success (more on that below).
Heart of Winter Successes and Failures
The
seeds were planted in flats and kept in our house
(not the greenhouse) until after germination and when the plants just
looked hardy enough to me to withstand cold temperatures. Our house
is not very warm (during this time of year, 60-70 degrees) but the
flats were in a sunny, south-facing window. I did not use warming
mats. In general, seed germination in the house was not a problem.
After about January, we tried germinating a few things directly in
the greenhouse pots and planters, with mixed success.
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A
table of planting dates, harvesting dates, and comments is shown
below, with further detailed discussion of each of the individual
plants below that. Note that while I’ll be discussing kale and
chard here, under the heart of winter plantings, those were holdouts
(well established) from a previous spring planting. I suspect that
kale and chard can be planted anytime during the year and do JUST
FINE. Similarly, one of the basils was a summer-growing transplant
that we just moved into the greenhouse for the winter. Our one
attempt to plant new basil in the heart of winter was a failure.
Details
for individual plants are given below.
Beets
We had great success with beets planted in March 2013 (right before the warm summer growing season) and also in December 2013 (during the heart of winter). The only problem with our beets was planting them too close together in a planter, which definitely stunted their growth when compared with beets planted randomly (and sparsely) in other planters. Heck, we plant everything too densely; that’s kind of our signature style.
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Broccoli
The broccoli was only a fair success. It grew well and produced florets, but I wouldn’t call it “vigorously” successful (note: I have not grown this variety before, so I have nothing to compare it to). Most likely it felt cramped by being too densely planted in a small rectangular planter box. In the planters, it may have done better. This variety (calabrese) does not make large bunches of broccoli florets, but instead produces lots of side shoots. The leaves, shoots, and florets are great in stir-fries.
Chard and Kale
The
chard and kale were planted long before the winter, in March 2013,
and flourished through the summer in the shady greenroom. They
likewise flourished through the heart of winter in the sunny
greenroom. Is it even possible to kill this stuff?
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| Kale. |
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| Chard. |
Leeks
The
leeks struggled to thrive, looking like scrawny stalks of grass for
quite a while. When the days lengthened and the temperatures climbed,
by around February (check), the leeks began to look much more robust
and started to look more like the size of green onions. They are also
probably planted too densely to grow huge and thrive (same old
story). We’ve been picking and cooking them young to help thin out
the pot. Leek is great in miso soup instead of green onions.
Lettuce
Lettuce
is an obvious success story for any winter greenhouse. It thrived. We
tend to plant “salad mix” seed packets in the rectangular
planters shown below. It takes about 1/3 to 1/4 of a planter to make
large dinner salads for 2, and we just mow down that portion of the
planter. By the time we get back around to that planter, it’s grown
back. We have salads for dinner at least 2 times per week all winter
long on our lettuce. We’ve been doing this since long before the
greenroom was built: with two rectangular planters in our sunny
south-facing windows, we could probably sustain 1 large dinner salad
per week from our greens alone for months at a time.
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| This is a lettuce planter that's been half shorn for a salad. The lettuce grows back at about the pace we eat dinner salads with two lettuce planters of this size. |
Hot Peppers
This
was a failure story that turned into a success story and continues to
astonish. I planted Hungarian Hot Wax peppers in small pots in the
greenhouse in November 2013 after the Thai hot peppers planted a
month earlier failed to take off. The little plantlings sat there,
about 3 inches tall with just a few leaves, from December through
February. Suddenly, it was as if a switch turned on, and the two
little plants we’d kept alive all winter suddenly started growing.
In March, they put on flowers. It is now early May and it looks like
we’ll be harvesting our first hot peppers by the middle or end of
May.
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| Peppers in May. |
The lesson here is to go ahead and plant in February, because they won’t do much during the heart of winter but they will take off as soon as the conditions are right, and we’ll be harvesting hot peppers long before the summer crops.
Radishes
The
biggest success of our greenhouse; we may become radish farmers.
Fortunately, we like them both raw (in salads) and pickled.
The radishes grew happily through the heart of winter, with plantings
in October 2013, December 2013, January 2014, and February 2014. We
enjoyed the “Cherry Belle” variety, which grew quickly and formed
nice round radishes the size of large gumballs. Another variety
(“Dragon”), planted in February 2014, has been much slower to
grow to maturity, so I can’t comment on the success of those yet.
They should form larger, carrot-sized radishes. Next year, I’ll try
other varieties during the heart of winter, but “Cherry Belle” is
a sure winner.
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Tomatoes
The
greenhouse tomato was actually a volunteer from our compost, and we
have no idea what variety it was. The pointy-ended fruit look like a
Roma tomato, or like a sort of pointy variety we grew a few years
back, but the tomatoes are very small. They may be stunted because of
the greenhouse conditions, but the plant itself grew humongous and
took over a whole planter.
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| Greenhouse tomatoes, May 4, 2014. |
Growing Failures
Basil,
Brussels sprouts, cucumbers, okra, parsley, peas, and thyme all
failed on us. That doesn’t mean they’re not possible for heart of
winter growing, only that something went wrong this time. (Some of
these, like cucumber and okra, probably are, in fact, unsuitable, but
I had to try.) Some of the plants that were failures as well as
semi-successes, like the Brussels sprouts, hot peppers, and leeks,
were incredibly slow-growing until January/February, and then they took off. The cucumbers
and okra sprouted nicely, but the little plants never developed above
a few inches tall, so eventually I let those die. The likely causes
of failure (or very slow growth) were length of daylight,
temperature, and pests. I don’t think water (too much or too
little) was a primary factor in any of the failures, but I could be
wrong. There may be other unknown causes of failure (e.g., bad seeds,
soil nutrients or texture).
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| The Brussels sprouts (far right of overcrowded planter) are finally beginning to grow after staying stunted all winter. May 17, 2014. |
Length
of Day
The
growing failures may have been caused by temperature or by hours of
daylight. Here’s a graph of the number of hours of daylight near
our location, along with the time of sunrise and sunset (note the
one-hour drop for daylight savings time!):
You
can see the hours of daylight (orange line) ranging from under 10 to
over 14 as the year progresses. When I planted the hot peppers in
November, the hours of daylight were minimal, at about 10, and that
includes dusk and twilight where the sunlight is extremely indirect.
In other words, just because the graph shows 10 hours of daylight, in
reality the hours of direct sunlight is far fewer.
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| The greenhouse at night. (We don't use grow lights.) |
Temperature
The
temperature was a problem, too. Okra, for example, needs warmth.
Peppers thrive with daytime temps above 80, and nighttime temps above
60-70. I think the nighttime temps may have been the clincher because
daytime temps were generally well
above 80 degrees F in the greenhouse. Nighttime temps were regularly
just above freezing, kept above the critical point by an electric
heater that turned on at 35 degrees F. Yearly temperature data are
coming soon.
Pests
Being
hot and humid, greenhouses are notoriously rampant with pest issues,
and I suspect this will be a frequent battle. Our greenhouse was
struck by a cabbage looper caterpillar/moth in December.
The cabbage looper attacked a few of the leafy greens – lettuce,
radish greens, kale – and, most sadly, the young pea shoots. The
pest makes its presence known by little black poops on the leaves (I
should have gotten a picture of that, sorry). The little bastards
were pretty easy to find and kill by hand, but they are green so they
blend in well and we never got a good handle on them by manually
picking them out of the leaves. Our usual go-to for organic pest
management, a diluted solution of Neem oil, was ineffective. Finally,
I got some advice from a local nursery and went with Thuricide, an
organic pest control method that only works for specific bugs.
Thankfully, it did the trick almost immediately, but not before we
lost all of our pea sprouts.
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| Cabbage looper. Killed by Thuricide. |
In
April, a fine, silvery webbing appeared around the chard, with little reddish dots in it (spider mites). A spray
of the diluted Neem oil solution once a day for 4 days took care of the problem (with just a single application, the mites returned).
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| Spider mites, killed with multiple applications of diluted Neem oil. |
We
had one more greenhouse pest problem. Note that some of the failures
in the table above are marked with the comment, “mangled by cat!”
This was a hilariously unanticipated problem: we didn’t realize
that the long, rectangular planters looked an awful lot like a litter
box. The cat spends plenty of time in the greenroom (in fact, she
thinks we built it for her) and naturally she was pawing around in
the rectangular planters until we figured out the problem and
chicken-wired off the lower rack of plants to protect it from the
feline.
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| We have to enclose the bottom-row plants with chicken wire to keep the cat out when the plants are little. |
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| Why, I would NEVER use a planter as a litter box and I resent the implication. |