I am thinking of putting some plants into my greenhouse to clear my dinning room table finally. I also want to start some more off in there too. Looks like the coldest at night will be +4 in the next week or so. Also fantastically warm tomorrow at +26. Finally our snow has gone. Just want to make sure I am not going to kill these pumpkins and water melons off moving them out there.
Is it safe to use the greenhouse yet?
- Thread starter Faith.M
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897tgigvib
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Do you have a hi lo thermometer in your greenhouse yet? Lacrosse brand is good and not too expensive, but make sure you save the manual for redoing it when changing batteries. They make them with remote sensors.
Are your temperatures Celsius or Fahrenheit? +4 sounds like 40 degrees or so.
Pumpkins and Watermelon will slow their growth a lot if under 40 degrees for very many days. Fahrenheit.
A propagation heating pad that uses 17 watts, cost about 30 dollars, would be a lot of help, especially if in the greenhouse you also have the plants under a mini greenhouse cover to help hold its heat.
A season extending greenhouse in a cold zone is best heated some way. Propagation pads and smaller enclosures inside it is a good start for that.
Are your temperatures Celsius or Fahrenheit? +4 sounds like 40 degrees or so.
Pumpkins and Watermelon will slow their growth a lot if under 40 degrees for very many days. Fahrenheit.
A propagation heating pad that uses 17 watts, cost about 30 dollars, would be a lot of help, especially if in the greenhouse you also have the plants under a mini greenhouse cover to help hold its heat.
A season extending greenhouse in a cold zone is best heated some way. Propagation pads and smaller enclosures inside it is a good start for that.
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digitS'
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Unheated, greenhouses can only advance the season a couple of weeks.
Heat and light -- glass or plastic film lose both. It used to be kind of a rule of thumb that a single layer of either cuts out 10% of the sunlight. That isn't too bad but 2 layers represents a 20% loss and on overcast spring days, that can amount to way too much.
My "sunshed" does a good job at gathering light and warms a good deal during the day. Even with an insulated north wall and roof, and with a concrete foundation, it doesn't hold on to much of that heat overnight. Some folks use water to hold heat. When I am desperate for additional room in there during the spring, I think about how the loss of space to a half-dozen barrels of water would make my life so miserable . . .
If you can get a thermometer into your greenhouse before the plants go in there and compare it to outdoor temperatures for a few days, you will have an idea of what the temperature situation will be. You may find that the temperature in there is just a few degrees warmer than outdoors by the last hours of darkness. At 4C(39f) there may not be much going on with plant growth overnight but they will be protected from frost. If it is an overcast day and the temperature in there is only reaching 10C(50f) during the day -- not much will be going on during the day, either.
It depends on the plants, cabbage & broccoli may be doing fine but pumpkins and watermelons will just be sitting there.
Steve
Heat and light -- glass or plastic film lose both. It used to be kind of a rule of thumb that a single layer of either cuts out 10% of the sunlight. That isn't too bad but 2 layers represents a 20% loss and on overcast spring days, that can amount to way too much.
My "sunshed" does a good job at gathering light and warms a good deal during the day. Even with an insulated north wall and roof, and with a concrete foundation, it doesn't hold on to much of that heat overnight. Some folks use water to hold heat. When I am desperate for additional room in there during the spring, I think about how the loss of space to a half-dozen barrels of water would make my life so miserable . . .
If you can get a thermometer into your greenhouse before the plants go in there and compare it to outdoor temperatures for a few days, you will have an idea of what the temperature situation will be. You may find that the temperature in there is just a few degrees warmer than outdoors by the last hours of darkness. At 4C(39f) there may not be much going on with plant growth overnight but they will be protected from frost. If it is an overcast day and the temperature in there is only reaching 10C(50f) during the day -- not much will be going on during the day, either.
It depends on the plants, cabbage & broccoli may be doing fine but pumpkins and watermelons will just be sitting there.
Steve
