Growing cool season lettuce

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Cool season lettuces and spinach in germination tray, ready to transplant into bigger pots

A friend of mine said the other night that she stopped trying to grow lettuce because it always gets too bitter. But growing lettuces in the spring can be easy-you just have to start earlier than you think you do. If you start seeds in late April, you’re too late as the weather can go from cold days to hot days very quickly and that is when they can bolt and become bitter so you’ll want to harvest earlier.

Since most lettuces are cool season crops and take around 45-55 days to mature, we need to back up our start date to sometime in February/March or even earlier inside under lights (like I did) and harvest in April or early May before it gets hot.

Be sure to grow lettuces that are cold tolerant-it should say on the seed packets. This year I started the first lettuces back on January 15 inside my house under grow lights with no heat-this is very early so I’m pushing it.

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Lettuce transplanted un into bigger pots or pony paks.

Then I transplanted them up from the germination tray into a pony pak on January 20. Then I  transplanted the plants into my greenhouse on February 17. That’s about 4 weeks old when I put them out in the ground.  My greenhouse is unheated so I have to cover them everynight and on cold days with 2 layers of row cover but so far they are doing well. Tonite is 13°F so let’s see if they survive…

Meanwhile I started more from seeds on Feb 03 and they were transplanted into the pony paks February 25 so if tonite kills the others in the greenhouse, these should go out into the greenhouse in another 1-2 weeks. Basically the whole process from starting lettuce seeds to putting out into a greenhouse or coldframe or as the season goes on takes about 4-5 weeks.

You can even put them in a raised bed or mini hoophouse with heavy row cover directly over them by the time April rolls around. So if you plant them in first week of March, you will be able to pick leaves 45 days later or around April 15. By the time everyone else is just starting their lettuce seeds, you will be enjoying the lettuces while they are sweet before it gets too hot.

Winter is Coming! (tomorrow nite-October 10)

As they kept saying in Game of Thrones, “Winter is coming” and it is coming here tomorrow night. Low temperatures tomorrow (Wednesday) will be 24°F and Thursday night will be 27°F. I’ve been harvesting everything I can before the cold hits. Afterwards is too late.

Most of my garden is done but here are some crops that may still need harvesting. I will pick my winter squash now and put it in the house. While winter squash likes it cold, it does not like the temperatures below freezing and can be ruined if they freeze–they should last months in the house.

Pick any green tomatoes of decent size and put them 2 layers deep in paper bags. The bags will keep the tomatoes in the dark. Then put a slice of apple in the bag (it releases ethylene gas, a natural ripening agent) and close up the bag to speed up the ripening process. Check the bag several times a week and you can move them to your kitchen table once they turn color. They are never quite as good as sun-ripened tomatoes but still 200% better than store bought and you may have home grown tomatoes into November.

Harvest all other warm season crops like beans, peppers, eggplants, corn, cucumbers, summer squash and melons-if they are not already picked.

Harvest onions if you still have any.

Cool season crops like broccoli, kale, cabbage, arugula and other leafy greens may survive but will need winter weight row cover over them to protect them from the below freezing nights. Take off in the day and recover at night when freezing. You can get row cover (winter weight) at some of the local nurseries. Just call around.

Beets and carrots should be ok but should be harvested before the ground freezes rock hard in December.

If you have lettuce, I would pick it as it will freeze. You may be able to save it with row cover over it, but it is chancy.

Herbs can be cut and dried in your house.

Of course if you have a cold frame, your season could still be extended if you cover the plants inside with row cover.

So pick everything you can today and tomorrow and don’t forget to disconnect your drip systems so they don’t freeze either. Get busy!

FREEZE ALERT!!

Starting tonight, the next 4 nights will be below freezing with the temperatures dipping down to 30°F tonight and 27-28°F for the following three nights so if you have anything outside or in an unheated greenhouse or hoop house or cold frame, you’ll need to put row cover over your plants to keep them from freezing at night.

Plant Greens in the spring!

April is a great time to plant greens like spinach, lettuce, cabbage and mustard greens. Plant now so you will get some greens to eat before it gets too hot. When it is hot they will bolt and become bitter. They can be grown in part shade to last longer when the heat comes. The spinach was actually started last spring and made it through the winter and the chartreuse and purple bok choi were put out 3 weeks ago. All are covered at night with row cover.

Other good crops to plant in April are bok choi and chard. They are real workhorses in the garden being able to withstand our cold and hot seasons. They can be grown in part shade to full sun.

Also good crops to plant in April are beets and carrots. Be sure to plant these in areas of your garden that are getting full sun and water 2 times a day until they are up.

Of course all this is dependent on your soil being warm enough now. How warm should your soil be? Between 40-60 degrees. How do you know how to tell? Get a soil thermometer and stick it in your soil about 2 inches deep. Here is a soil temperature chart to help you know when to plant veggies.

And these plants should still be covered with row cover at night because of our cold temperatures.

 

Watering in early spring- how much in a greenhouse, hoop tunnel, or cold frame?

Just got a great question from the earlier post. How much do I water in winter-early spring in my greenhouse? Not very much. Since I don’t have the drip systems on and I don’t want to empty hoses that might freeze, I fill up 5 gal buckets, leave them inside the GH and then fill up my watering can from them and water the plants. Five gal buckets are kinda heavy for me (40 lbs) so I prefer to transfer the water to a watering can. Or just fill up a watering can from your house and refill as needed. The only problem is my greenhouse is too far from my house to keep refilling a watering can from the house. Notice the white row cover on the side, ready to go back on the greens tonight when it gets cold.

This time of year is called the ‘shoulder season’—not quite winter and not quite spring-with extreme temperature swings from day to night. There is no set formula for watering because one day the temperature can be 60°F and the next day in the 40’s°F or even 30’s°F. Same with nighttime temperatures.  Or you structure might really heat up in the day if you forget to open the doors or plastic on the ends or open the cold frame. So there are lots of variables that will affect how much to water. I really watch the plants and the soil in regards to watering when I have to do it by hand. Does the soil appear damp after your last watering even though its been maybe 4-5 days? Don’t water. Do the plants look like they need water? Are they looking stressed? Wilted? Water! The cooler it is, the less you have to water. I don’t water till the soil FEELS dry when I put my finger in it around a plant. But I can tell you this, you will be watering much less than in the heat of summer.

 

Cool season crops have begun

transplants-2-weeks-old

When I was looking through what I plant each year, I realized I actually grow many varieties of cools season crops (like greens/lettuce). I started some seeds of cool season crops inside under lights but no heat on Jan 17!  I never put the heat mats on for cool season crop seeds, only for warm season crops and it is way too early for them just yet.

I started:
Asian greens: bok choy, pak choy, Wasabi arugula

Lettuces: 4 Season Lettuce butterhead, Yugoslavian Red butterhead, and Santoro butterhead lettuce. Can you tell I like butterheads?!

Leeks: Solaise, King Richard and American Flag

Onions: Candy (it is an intermediate or neutral variety) which is they type of onion we have to grow here.

Spinach: Carmel-Just planted the seeds today. Still have some spinach plants that have overwinter nicely outside in a raised bed with only winter weight row cover on it. By planting a crop of spinach last fall, I’m hoping I get a bumper crop of spinach in March! The variety of spinach I like the most is called Carmel which overwinter last year and looks to do the same this year. You can get seeds from Johnny’s or plants from Agua Fria Nursery.

4-season-lettuce

four season lettuce is looking good

Today I transplanted up lettuces and Asian greens to pony pots from seed trays. The plants are looking good but need to grow more before I put them out in my green house or cold frame. You can plant outside in sunny raised beds in March but all-greenhouse, cold frames or just plain old beds will need winter weight row cover on the little starts to protect them from our cold nights.  I’m hoping to put them out by beginning of March. The varieties I grow at this time of year are very cold hardy. I’m trying to get a head start as our cool season crop season is pretty short here before it gets too hot and everything bolts. And there is nothing better than spring spinach or lettuce!

More daylight hours/plants start to grow again

Growing Spinach and Lettuce in a Cold Frame

The Persephone period is over. Elliot Coleman in his Winter Harvest Handbook, coined this name. When daylight hours are less than 10 hours per day, the plants that are in the ground slow down or stop growing altogether during this time. This means that the spinach or mache you planted last fall had slowed down and by Thanksgiving stopped growing. The Persephone period can be longer or shorter depending on what latitude you live in. For us in Santa Fe, it is from Thanksgiving to Jan 14th.  In states that are further north, they are still in the Persephone period. As the daylight hours continue to get longer and longer, you should notice the plants starting to grow again. I grew ‘Carmel’ spinach last fall in one of my beds up by my house and it is still alive, covered with winter weight row cover. I did this the year before and it survived and gave me beautiful spinach by March that I was able to harvest 4 times before it became too warm. If you didn’t grow anything to overwinter, you can now start spinach, Asian greens like ‘Tatsoi‘ and ‘Baby Bok Choy’, mache and some very cold hardy lettuces like ‘Winter Wunder’ and ‘Marshall Red Romaine’ once the soil warms to 40•F+. If you keep them covered with winter weight row cover to protect them from our cold nights, you will be able harvest them in early spring barring any devastating deep freezes. If you can’t wait and want to speed up the process, start the seeds under lights inside now and transplant them next month in February. To find other extra cold hardy crops to grow, go here.

Extending the Season-Making a Low Tunnel

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These broccoli transplants were put in on Aug 24, 2106

I taught a class in late August on Planting for a Fall Harvest where I showed the students you don’t have to have a Greenhouse to extend the season. You can also have a cold frame or even simpler is what I call a low tunnel. Now with the cold nights, you definitely need something over your new fall transplants.

low-tunnel-before-row-cover

Here is the frame of the low tunnel before row cover-just fencing material curled into a u-shape ready for plants underneath it

I like to make my low tunnels out of 2″ x 4″ fencing or even concrete reinforcement wire.  I just open up the fence roll, cut off enough so it will be curved above my plants and turn it upside down on the soil.

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row cover over the low tunnel protects crops at night

Cover it with winter weight row cover (1.0 ml).  I put rocks on mine to keep it from blowing away. Now you have a secure low tunnel that will protect your plants during the shoulder season that is closing in on us quickly. What is a shoulder season? It is the time of year when the temperatures can drop quickly at night near freezing and then heat up in the day. The temperature shifts can swing wildly during the shoulder season. We have a shoulder season in spring and fall. By making a low tunnel, you can extend the season and grow vegetables like spinach, arugula, kale, lettuce, bok choy, mustard, mesclun, radicchio and other cool season crops much later. Fall is a great time to plant cool season crops and it’s not too late if you get transplants now. It might be too late if you start from seed unless it’s lettuce. Try to pick varieties that are cold tolerant.

Gardening this spring

trini

But first one last memorial-I couldn’t resist because I found this photo. I haven’t written much lately because I’ve been sadden by the death of my favorite kittie-kat, Trini. Above is a photo taken by Genevieve Russel several years ago when Trini was younger that I just found and wanted to share. Wasn’t she beautiful? She had a heart of gold too. She would let you do anything to her-toss her around, make her dance or dress her up in doll clothes and put her in a high chair (Flynnie did that years ago). I even made her play the drums with me once! And whenever you answered the phone, there would be Trini, meowing loudly in the background so as not to be ignored. Absolutely had no boundaries (which is unusual for a cat). We have two other kitties (with boundaries) who would never let us do any of those things (probably claw our eyes out), who are wonderful too, but Trini was a very special being.

But I haven’t been sitting around either. I’ve been sooo busy finishing planting cool season veggies outside in the greenhouse and coldframe, and doing succession planting of more lettuces as I use them up. Here’s what’s been up around the farm:

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Wrapping up all cool season crops-lettuces, bok choys, kale and chard are going outside either in the greenhouse, cold frame or in the main garden. Many have already been growing (and eaten). Pictured above, my coldframe shows lettuces, cilantro and bok choy ready to harvest. As we eat them, new ones go in any empty place. This cool spring has been great for the cool season crops this year. Absolutely no bolting yet-wonderful! Notice the bamboo shade screening on the outside of the top of the coldframe. It was cut to size and screwed on and provides wonderful shade to help keep the plants cooler and keep them from bolting. I won’t be planting any more lettuce greens for a while, but when I do, it will be with HEAT TOLERANT lettuces for summer outside in the shade. Besides I have enough to eat for at least a month…

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Here are some other lettuces inside the greenhouse we’ve been munching on since winter. This variety is ‘winter wonder’. I’ve already harvested a bunch and will soon finish it as this variety likes cooler weather. In case you’re wondering, that hardware cloth in the pic above the lettuce, is a lid covering all those beautiful lettuces. I propped it up to show the lettuces. I built it to keep the mice from eating them first. Last year was terrible for me and great for the mice-they ate anything young or tender. The lid is working-no lettuce has been eaten in the greenhouse by mice, only me! Haaa!

BT in GH

But maybe the presence of one of our cats, BT (broken tail-hey we didn’t do it, we got him that way!) the great mouse hunter, also has been an influence on no mice in the greenhouse! Here he is checking out my building skills.

Bt in lid

And here he is trapped in one of the lids!

 

spinach spring

 

spinach bed with shade clothWonderful spinach-this variety, Carmel, shown above has some radishes growing with them. You can still buy starts from Aqua Fria Nursery but soon the spinach season will be over so don’t plant by seed now. To extend the season at this time of year, I put a shade cloth over the bed (right) so they will last a little longer and not bolt. Meanwhile the spinach has been wonderful with this extended cool weather we’ve had. Better enjoy it now as it’s gonna get warm soon.

 

kale floweringLast year’s kale is toast. Finito. The pic on left shows them bolting (flowering) and putting all their energy into making seeds and fighting off the aphids. Kale is a biennial plant, meaning they will live two years, putting most of their energy into making leaves the first year and making seeds the second year. Since I don’t want to keep the seeds this year (I have plenty), I will pull them and give the plants to my chickens after they finish flowering (the bees like the flowers). The chickens will enjoy the kale and get extra protein with the aphids-perfect. Otherwise if I had no chickens, I would be composting them. There would be no problems with the aphids as they need living plants to feast on. In the compost pile, as it heats up, they will become toast anyways (I like that word)! But don’t worry, I have another crop of kale going in this week!

red orach reseeded

In the left pic is Red Orach. Plant it once and you’ll have for a lifetime. It readily reseeds itself. It is very tasty—kinda like spinach (in the same family) so you can cook it or put it into salads. Here it is growing willy-nilly everywhere.

 

garlic and shallotsIn the right pic is garlic growing nicely. Planted it last fall and mulched it with straw to help keep moisture in the soil. It’s not a cool season crop but does come up with the other cool season crops. I bet you wonder why I have a ladder across the bed-well it is to keep the neighbor’s dogs off of it and it works! They use to come over and lay or wrestle on top of the garlic and straw and now they don’t bother it at all.

rhubarb spring

And let’s not forget rhubarb this year! Mine is up and I’ve already cut off the flowers so all of their energy will go to the leaves and stalks. Only eat the stalks as the leaves are toxic. They have concentrated levels of oxalic acid in them.  How toxic? I don’t know how toxic for humans but I once saw a dead mouse who ate part of a leaf and died under it! Soon there will be rhubarb-strawberry pie-yum!

 

potato bags in herb garden

Finally I planted some of the potatoes in ‘potato gro bags’ in the herb garden. Can’t wait to see how they do! These are “purple’ potatoes whose variety name I can’t remember, but they are a fingerling type. The herbs are doing well too. This is the second year for these perennial herbs. There is marjoram, oregano, kitchen sage, winter savory, thyme, chives, tarragon, lemon thyme and garlic chives. We beefed up some of the drip system so they should get plenty of water this year. Lavender is in another part of the garden and lots of basil will go down in the main garden later when it warms up!

 

Lettuces to grow in winter

lettuce-jan 16, 2015

Here is some lettuce I harvested from my unheated greenhouse on January 16th! I’ve been experimenting growing some cold hardy lettuce varieties (Winter Wunder and Marshall Red Romaine) this winter.  I told you I would report back and here is my first harvest. I find it amazing that they survived some very cold nights 6 to 8°F (-14 to -13°C for my European friends) in the greenhouse with only some winter weight row cover over them for added protection. I planted them from transplants instead of seeds in November so they had a good head start. It’s really fun to see something ‘green’ growing this time of year and yummy too.

 

 

 

 

 

Starting COLD HARDY VEGETABLES Super Early

lettuce_greenhouse germinating

So now that the Persephone period is almost over and the magic date of January 15th is upon us, what does that mean? It means our day lengths are getting longer and January 15th is when we start getting 10 hours of daylight that will continue to get longer every day. Have you noticed already it now gets dark around 5:30 instead of 5 pm? The darkest time of the year is over. What does that mean to gardeners? To learn how to start cold hardy vegetable seeds super early outside and how also how to start them inside read on.

STARTING COLD HARDY VEGETABLE SEEDS OUTSIDE: cold frme opened
If you want to try growing cold hardy vegetables outdoors at this time of year, you will need a cold frame, low tunnel or hoop house.

If you already planted cold hardy vegetables late last fall in a cold frame, low tunnel or hoop house, you may have noticed that the little seedlings haven’t been growing much at all as winter set in. Now with longer daylight hours, they will start to grow again and barring any devastating freezes, they will continue to grow and you can get cold hardy crops earlier this spring.

In late winter, before you have harvest your winter crops, decide what you want to plant in your bed once space opens up in your cold frame.  As the end of the Persephone period draws near (January 15) , you can re-seed the openings created from your harvesting or you could start planting seeds in your bed if you don’t have anything growing. My soil in my unheated greenhouse is at 40°F right now (as of January 12). Lots of cold hardy vegetables germinate in cold soil.  They will be slow to start at first but they will start as your soil warms up to 40°F and warmer. Now with the day light getting longer, you can think about starting early. The winter sowing you do will be ready for harvest by early spring, often long before the same crop when grown outside without protection. A bonus is many of the cold hardy winter crops don’t like our springs, bolting on the first few warm days so you’ll be able to harvest that spinach before it bolts!

Some cold-hardy plants planted inside a cold frame, low tunnel or hoop house can tolerate a hard freeze at night, provided they are allowed to thaw during the day. The plants must be completely thawed before you harvest them. In addition, put some winter row cover over seedlings at night to give them an additional 4-6°F protection even though they are already in a cold frame, etc. Remove the row cover on days when it is above freezing. Watering is necessary to get crops started, but they will generally need very little water during the winter season-early spring once established.

STARTING VEGETABLE SEEDS INSIDE:
I’ve already written about starting seeds inside on many earlier posts.
To learn all about starting seeds indoors to get a head start go here:
https://giantveggiegardener.com/2012/03/08/starting-seeds-inside/

WINTER HARDY VEGETABLES
The following list of winter vegetables to grow is from ‘The Winter Harvest Handbook’ by Elliot Coleman. These can be planted either as transplants (first started inside under lights) or outside as seeds in cold frames, low tunnels or hoop houses.

Asian greens-Tatsoi, Pak Choi (Mei Quing Choi), Mizuna, Tokyo Bekana,Komatsuna

arugula-Astro, Sylvetta

beets-Red Ace, Merlin, Touchstone Gold

beet leaves-Bull’s Blood, Red Ace

carrot-Napoli, Mokum, Nelson

chard-Fordhook Giant, Ruby Red, Argentata

claytonia

endive-Bianca Riccia

leek-Tadorna

lettuce-Red Saladbowl, Tango, Rex, Rouge d’hiver

 mache-Vit

minutina

mustard green-Toyoko Beau

radishes-Tinto, D’Avignon, Cherriette

scallion-White Spear

sorrel

spinach-Space

turnip-Hakurei

watercress

Spring has sprung! (well almost)

lettuce_greenhouse germinating

This lettuce is from Johnny’s called All-Star Gourmet Lettuce mix coming in the greenhouse.

In celebration of my FIRST CROPS coming up in the greenhouse, I’ve changed the background color on my blog back to green from winter blue. In my mind, winter is over although not officially – that won’t take place till the first day of spring on Spring Equinox on March 20 and of course we can still (will) get snow. No matter. I’m ready! I’m moving on and planting stuff (in the greenhouse). What kind of stuff? Read on to find out!

bok choy_yellow green

These are a golden yellow pak choi (shakushina) from Kitazawa. They’re already a great yellow-green color and will make a wonderful contrast to the tatsoi.

These first crops took about 12 days to germinate-they actually came up on March 1 so they were planted on Feb 17th. They are all still tiny but coming up nicely. The top picture is a lettuce mix from Johnny’s called All Star Lettuce Mix that’s suppose to grow out evenly. The second picture is a golden-yellow pak choi (shakushina) from Kitazawa. Also from Kitazawa are Pak Choi rosette (tatsoi) and white stem dwarf pak choi (both not shown). These were all recommended in Elliot Coleman’s book, Four Season Harvest (except the golden-yellow pak choi which I couldn’t resist because of the color). According to Elliot Coleman they all do well in cold greenhouses.   I have winter weight row cover over them now to protect them at night. I also planted Winter Bloomsdale spinach from Southern Exposure Seed Exchange at the same time and it’s coming up way slower but the first 2 seedlings broke ground yesterday, on March 3.

Ah, spring has sprung-and we got rain this week! What could be better?! I’m also going to plant transplants this week to see how they do in comparison to the seedlings. I’ll get pics later on that one.

Early Spring Planting-Three Important Factors

Three important factors should be considered before planting seeds in early spring:

Amount of daylight hours-In the winter the sun is weaker in the northern hemisphere and we have less daylight hours. If you plant seeds too early either outside or in a greenhouse, the seedlings will be spindling when they germinate. Once we have 10 hours of daylight (we currently have over 10 hrs), we can start planting our cold hardy seeds. So in Santa Fe, we now have enough daylight hours. But wait, there are several more factors we need to consider before we plant seeds.

Soil temperature for germination for different vegetable seeds

Soil temperature for germination for different vegetable seeds

Soil temperature-If you are thinking of planting OUTSIDE, forget about it, your soil is probably frozen so of course you can’t plant anything! Even if it’s not frozen, it’s probably still too cold to plant outside. However it will warm up soon. How can you tell what temperature your soil is? You’ll need a soil thermometer. I prefer a compost thermometer that is about 18″ long so you can check both the soil and a compost pile. A soil thermometer is invaluable, as different veggies like to germinate at different soil temperatures. Insert it about the depth of the root zone of the plants, about 4”-6″ in the soil to see how warm it is. Notice the chart above gives an optimum range for each veggie.  If you have a cold frame, hoophouse or greenhouse your soil is probably much warmer already. So are you ready to plant? Not quite. There is one more factor to consider.

Air Temperature-The air temperature is also important and is the main thing people think of in considering when to plant seeds. It’s too cold at night to plant most veggie seeds outside or even in a greenhouse without extra protection BUT there are some wintergreens that are very cold hardy, some even hardy below 32°F at night. Even in an unheated cold frame or greenhouse, the temperature dips below freezing at nights so if you have a one, I suggest you put some row cover (winter weight-.9-1.0 mm.) over your beds. If you don’t have a greenhouse and will be planting outside in early spring, definitely put row cover over it at night but don’t forget to check your soil temperatures too.

I’ve compiled a list of these very cold hardy crops that can be started in a greenhouse now if the soil temperature and daylight hours are good. Many of these cold hardy crops can be planted outside as soon as the soil warms ups in March. For the list go to my blog at: http://giantveggiegardener.com.

Cold Frame Survivors

I tried to overwinter some veggies in the coldframe that I planted last October. I wanted to see what would survive and what would die back.

coldframe survivors

Here is what has survived (so far) in the coldframe – 1 sad little bok choy, 2 sadder lettuces, 4 happy endives, a row of Bull’s Blood beets and 2 chard. The mache and arugula were doing great but bolted during the 70°F day we had last week and were loaded with aphids so I pulled them out and the chickens enjoyed them instead of me. What didn’t make it was some of the chard, most of the lettuces and mesclun (more baby lettuce).

Now it is suppose to get down to 16°F tomorrow night and 14°F on Sunday night! Yikes! I’m going to spray everything with insecticidal soap for 7 days in a row to hopefully rid me of the aphids. I don’t dare plant anything else in the coldframe till I’m sure they’re gone.

I also planted spinach in an outside raised box with row cover over them and they hung on in a rather dormant state and now they are growing full blast.

Next year I will only plant endive, mache, spinach and arugula as they did great even when we got down to 10°F although I do put a layer of heavy row cover over all when it gets down in the teens.

Univent Automatic Coldframe opener

I just got a Univent automatic opener that opens and close a cold frame lid. I’ve wanted one for a long time. This will save me time running out and opening it on a warm fall day (so my veggies don’t cook) and then running back and closing it when it gets cold later in the day (so they don’t freeze). It is a temperature sensitive opener designed to open windows in greenhouses or lids on cold frames. It can be adjusted to start opening between 60-75°F. It fully opens at 86-90°F up to 18″ and fully closes at 55°F.

Here is a little info from ACF Greenhouses on them- “How do automatic vent openers work? Vent openers do not require electricity. The opener has a metal cylinder containing a mineral which expands when heated. This pushes a piston that opens the vent. As the temperature cools, the mineral shrinks and a spring closes the vent and resets the piston. The opening and closing of the vent is gradual allowing just the right amount of air flow for cooling.”

You can get them from ACF Greenhouses or I got mine from Peaceful Valley. Now all I got to do is get my fall greens in!