This year’s early lettuce…

This year's early lettuce...

The end-of-March scene in the greenhouse is a lot different than last year, when the growing area was neatly filled with early lettuce. This time around, the early effort has turned into a much more spotty affair. The lettuce started WAY early at the end of January, and held back because of extreme cold earlier in the month, grew and REALLY stretched in the trays, and I only put about half in the ground, just to see what’ll happen. Filling in, there are a couple of beds of direct-seeded, all-lettuce mesclun. The idea of making it to the first market day (this year, it’s Saturday, May 3) is fine if everything else is humming along, but given the slow-leaving winter this year, chances are I’d rather be in the field or doing some other outdoor stuff on the farm at that point than spending a good part of a May day at market with a small quantity of greens, just for show. With this year’s early lettuce and the weather, I’m no longer in such a rush!

7 thoughts on “This year’s early lettuce…”

  1. Mike,

    What are your min/max temps in the greenhouse? I tried looking back to see how you regulate temps. I brought flats out to my unheated high tunnel and they look terrible. They were only in the tunnel one night. The temp was 98F when I arrived the next day (I live an hour away) so I immediately rolled up the sides a bit till it stabilized at 70F. I left the sides rolled up a few inches despite freezing night temps as I would not be able to be there this morning.

    I checked them at 3 this afternoon and they look awful. Most were onions and flowers. So I can’t figure out if it was too hot or too cold. Would you recommend putting a min/max thermometer right next to the flats?

    By the way, your stuff looks great.


  2. we just seeded 2 beds of spinach (50ft x 3rows) and 1 bed on mixed lettuce (50x 3 rows) in our unheated greenhouse …..this is later than usual but if the weather continues to warm up we will be on track.
    we also seeded beds of radishes and onion sets.

    our local farm market opens may 10th …..i should have greens etc (hopefully) …as well vegetable,herb and flower transplants

    your greenhouse sure looks tidy

  3. julie: I really rough it with the hoophouse. and the conditions in there can be pretty extreme. From March through August or so, when the sun is high and strong, on a sunny day, it’ll rocket up to 120°F (45°C), and go down to outdoor temperature as soon as the sun sets.It’s not so bad on cloudy days, maybe 80-90°F.

    I’ve never rolled up the sides, I can get by because it’s usually empty by the end of May and so far I haven’t grown anything in there during the summer (too small). For ventilation, there are the doors at each end, and windows above the doors, and a not-very-powerful fan.

    Moving out trays started indoors, I treat different crops a bit different, but overall, it’s a pretty hardcore approach lately. I used to harden off over 4-5 days, but that was taking up way too much time. These days, I’ll usually wait for a cloudy day and then just put ’em out. Or give them one or two days of 2-3 hours of morning sun, then outdoor temperatures in the shade of the barn, indoors at night, and then move them to the greenhouse. When there’s sun, for the first few days, I’ll put ’em under a couple of layers of light row cover. Last year, for tomatoes and peppers, I hung a piece of 50% shade cloth for a few days. And they need lots of water, with the heat and if you have a fan going as well.

    I wouldn’t recommend this as a…method, but it works out for me while I work on better shade and ventilation. Meanwhile, you also develop a bit of a feel for each crop and how they react to conditions, which is what I mostly rely on. So I may be shocking them sometimes, but I don’t lose anything.

    I always have a min/max thermometer out there, check and reset it every morning and evening, but it’s more to get a sense of the range, just a learning thing, than to take any action on. Sometimes I’ll put a second min/max under row cover, to see the difference.

    Dunno if that helps?

    cathy: That sounds great! I’ve been looking forward to a production-size greenhouse. Maybe this year! The seedling greenhouse is only 20×32, not much growing room, and I may have to add more seedling tables this year.. You’re seeing the tidy side!

  4. If you have a lot of barrels lying around you could try some passive solar heating by filling them up with water and letting them absorb the high heat during the day and reradiate it at night…but it could take quite a few to make a dent in the cool temps. Don’t know the calcs on that. A little heater set on low to keep temps above 40 F might not use too much energy(?).

  5. thank you for the ideas. These seedlings were not that vigorous to begin with. I am going to try starting them in the tunnel; and see if germinating and growing in the conditions helps toughen them from the get go. Some of the lettuce started in the house is so stretched it isn’t worth putting them out.


  6. I’ve had some little Winter lettuce seedlings in the greenhouse for months.. they just sit there and do nothing. I think they are just lazy!


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