We’ve just got a few months left in my monthly series of 14 Workhorse Crops (asparagus, beans, cabbage, carrots, chard, collards/kale, garlic, potatoes, sweet corn, sweet potatoes, tomatoes, watermelons, winter squash, zucchini/summer squash). These crops are reliable and productive under a range of weather conditions. You can use the search box to find other posts in the series, such as February.
Spring is on the way! Many more crops to plant this month! Our average last frost (over the past 14 years) here in central Virginia is April 29. We reach 11 hours of daylight on February 20, and we and everyone else will reach 12 hours on the March 20 Equinox. It’s all go!
In our hoophouse we are clearing bolting crops and transplanting spinach (the “Racehorse” of this series) wherever we have space along the edges of the beds. The tomatoes go in in March and squash, cucumbers, and peppers in April. Those crops will occupy the centers of the beds, before taking over the whole width. Our greenhouse is filling up with transplants.
Workhorse Crops to Plant in March
We transplant our early cabbage around March 6. We had trouble with mice in the greenhouse in early February and lost quite a few seedlings. We also made the mistake of using seed that was too old. So we will have only one bed of early cabbage this year, not two. We did try to make up for the losses by resowing fast-maturing varieties, but we still ended up short. We like Farao (60d) and Early Jersey Wakefield (63d). Both numbers are seed to harvest. Subtract 20 days if counting from transplanting to maturity. We will cover the bed with thick rowcover for the first few weeks after transplanting.
We sow carrots in mid-March, and again at the end of March. The mid-March sowing takes from 9-19 days to germinate, depending in on the soil temperature. The end of March sowing takes 9-12 days. We sow a few Indicator Beets at the beginning of the bed. Beets germinate one day sooner than carrots at almost any temperature. When we see the red loops of the beet stems emerging, we know it’s the day to flame weed the carrots.
We sow chard (and leaf beet, the type of chard closest to spinach) on March 24, but you can start earlier if you want earlier harvests. Chard seed will germinate from 41°F (5°C) to 95°F (35°C), and the best temperature is 86°F (30°C), when it needs only 4 days. Our goal is to use chard as our main summer leafy green after the kale, collards, broccoli and Asian greens have all bolted. In spring we usually have lots of cabbage, broccoli, collards and kale. Maybe we should do some earlier chard this year to make up for lack of broccoli and troubles with cabbage and over wintered kale?
Collards and kale
In mid-March we will be transplanting Vates kale and Champion or Georgia Green collards directly from the soil in our hoophouse out into the garden. We usually grow Morris Heading collards but this year we are trying something different. We’ll use rowcover for the first few weeks. I have written before about bare-root transplants. This method saves us a lot of time, and saves greenhouse space. See Workhorse Crops in February for details about sowing these crops in the hoophouse.
Another mid-March task for us is potato planting. I wrote a whole series about every stage of potato growing last year. So I won’t say more here.
We don’t grow green bush beans in our hoophouse every year, but this year we will. As with other late winter/early spring hoophouse crops, we sow beans in our hoophouse a month earlier than we can sow outside. We aim to sow in the hoophouse on March 20. Of course, if it is particularly cold then, we will wait. We’ve found that beans sprawl more in our hoophouse, so we buy an upright fast-maturing variety, such as Strike. We’ve also found that the edge beds are too cold for beans in late March, so if the crop rotation would have us use an edge bed, we sow beets or some other crop instead. We will use thick rowcover on nights that are forecast to be frosty outdoors. See mention of hoophouse beans in January.
Mid-March is our target transplanting time for tomatoes in the hoophouse. We grow two beds, one of earlies (less than 71 days) and one bed of reliable favorites (Tropic, Jubilee) along with two plants each of other varieties we like or are trying out. Each 96ft (29 m) bed has two cherry or grape tomato varieties, with two plants of each. We plant the shortest varieties at the east end and the tallest (the cherries) at the west end, so that all the plants get the best possible light. (Our hoophouse has the long walls on the south and north.) We update our Tomato Rampancy Rating list each year.
This year in the early bed, we are growing Five Star Grape 62d, Sun Gold 57d, Garden Peach 71d, Mountain Magic 66d, Stupice 62d and Glacier 56d. Mountain Magic is a new favorite (it doesn’t suffer from green/yellow shoulders) and we have increased the number of those plants, reducing numbers of Stupice and Glacier.
In the other bed we are growing Cherry Bomb 64d, Black Cherry 64-75d, Geronimo78d, Striped German 78d, Amy’s Sugar Gem 75d, Green Zebra 72-86d, Cherokee Purple 72-85d, Tropic 80d, Jubilee 80d, Estiva 70d, Pink Boar 75d, and Mountain Fresh Plus 75d.
We use the Florida string-weaving (or basket-weaving) technique to support our plants. More about that task in future.
Indoor sowings for later transplanting outside or in the hoophouse
In March we will sow our hoophouse cucumbers and squash, and our outdoor peppers, eggplant, maincrop tomatoes, and our first outdoor zucchini and summer squash. And some non-workhorse crops. Also, we start our sweet potato slips. I covered growing sweet potato slips in another post. On March 24 we start our chard, as already mentioned.
Workhorse Crops to Harvest in March
Collards and Kale can be harvested outdoors here in March, from overwintered plants. This past fall, we were late getting our kale established and the combination of a mild December and a cold January has damaged them badly. We had 3 nights in January down to 10°F (-12°C). Normally we can harvest those beds once a week each in March. Our mnemonic for sustainable harvesting of leafy greens is “8 for later”, meaning we leave at least eight inner leaves when harvesting the outer ones, to ensure the plants have enough strength to regrow.
Overwintered Carrots and Cabbage are a possibility some years, but not this one!
Garlic scallions are ready to harvest here from mid-March. These baby garlic plants offer a welcome change form leafy greens and root vegetables. We start to dig the plants once the leaves have reached 7” (18 cm). Wash and trim, cook and enjoy! Yes, you can eat them raw if you like! Some years we have made a big planting, and it has provided for us into May (when they are starting to bulb).
Hoophouse Workhorse Harvests in March
Our Red and White Russian kales are now producing well. These are Siberian-type kales, that keep growing (a bit!) in cold weather. We harvest the outer leaves and stand them on end in a bucket in a little water. The wilt very easily, so we try to keep them in the shade and get them to the cooler promptly.
Bulls blood beet greens, chard, and some greens not in our Workhorse group, (turnip greens, and spinach) are still going strong. Our experimental carrots are still doing OK, although I’m not a fan of giving them hoophouse space for such a long time with no harvests. I think we would have done better to harvest them in December. The foliage is getting bedraggled, and I fear the roots are getting woody and less sweet. This is all an experiment by one of the others on the crew, who will be studying the results.
Workhorse Crops from Storage in March
In March we can eat carrots, garlic, potatoes, sweet potatoes, winter squash and cabbage from storage, while they last. We do still have potatoes, sweet potatoes and butternut squash. Also we have frozen summer goodies, and pickled things, sauerkraut, pickled beans, and canned goods like salsa.
Workhorse Crops Special Topics for March: DIY Weather Forecasting
Learn your local weather patterns by keeping records of daily max and min temperatures and rainfall, and watching what happens.
Our mid-Atlantic climate is controlled by three weather systems, mainly by moisture from the Gulf of Mexico, the Bermuda High Pressure area in summer, and recurrent waves of cold Canadian air in winter.
Rain (statistically fairly evenly distributed throughout the year in our county) has slight peaks in January, February and March and again in early June and August.
Some parts of our area can experience long periods of drought: September-November is the drier season but it’s also the hurricane season, so the net result is very variable.
We use Wunderground forecasts, but subtract 5F° (2.5C°) from their forecast night lows for our nearest town, and mentally downgrade the chance of rain by 10%, as rain often passes us by as it scoots along the river valley north of us. 3/30 pm in winter is a good time to look at the night forecast.
WeatherSpark is a great resource. You can enter your zipcode or town and discover a large range of charts and graphs about weather in your area. It will help you learn what to expect.
As for predicting frost, here are some of the factors to consider, that make frost more likely here:
- If the date is after 10/14 or before 4/30 (ie within the average range for frosts here)
- If the Wunderground forecast low for Louisa Northside is 37°F (3°C) or less.
- If the daytime high temperature was less than 70°F (21°C).
- If the temperature at sunset is less than 50°F (10°C).
- If the sky is clear.
- If the soil is dry and cool.
- If the moon is full or new.
- If there is little or no breeze, although if temperatures are falling fast, the wind is from NW and the sky is clear, then polar air may be moving in, and we’ll get a hard freeze.
- If the dew point forecast is low, close to freezing, a frost is more likely. Frost is unlikely if the dew point is 43°F (6°C) or more.