Greenhouse Advise Needed!!!

[Dawningstar1]

Hi I have a large greenhouse here, just moved here this past Oct. so I am truly really new to greenhouse growing lol...

Now, last year I grew my seeds in pop bottles, the plastic kind first the 750 ml then into the 2 litre size this made the stocks really strong, my tomato plants were then transferred outside in June, the cherry ones reached at least 10 feet high, lol could have been higher as they grew up into the neighbors tree lol she used a ladder to pick em....

So, growing isn't very difficult except this year I am in a small house but have a huge greenhouse.... so my questions are

1. When should I start my seeds lol.... we have some bad storms in Feb. and in March up here!!!

2. Are there certain types of seeds that do better??? Most of the time I save my green peppers and tomato seeds, if I happen to buy a tasty tomato I try to save a few seeds from them...

3. Does the type of greenhouse make much difference??? I figure the glass ones would be colder, mine is made with thick white plastic commercial grade... the ground inside is sandy dirt and has not frozen yet!! Wondered if anyone with one of these types of greenhouse have started seeds when snow is still on ground outside!!!

Any help would be greatly appreciated thanks in advance!!!

[amideutch]

Welcome to Tville and I'm sure one of our many Canadian members will chime in. It might help if you tell us where in Canada your located. Ami

[Fusion_power]

I posted this at another website a few weeks ago. The basic advice is good, but please remember that you are in a much colder climate with a longer interval before summer.

The first rule of a greenhouse is to understand that air circulation is critical. You need a fan, it should be sized for the greenhouse you are using. My greenhouse is 23 X 32 feet and I use a standard box fax that is about 2 feet across.

The second rule is that you MUST have some way to heat a greenhouse if you plan on growing tomatoes and peppers. An electric heater or gas heater on a thermostat will work for you. Caution that tomatoes are VERY sensitive to gas in the air so be sure to have a reliable non-leaking system. As above, it should be sized for the greenhouse.

Now think about what you want the greenhouse to do for you. You can grow early starts of peppers and tomatoes at any point you want them. I would suggest starting off with seeding hot peppers about the 1st of March , sweet peppers about the 15th of March, and tomatoes about the 1st of April. Start them inside the house where you can control germination temps to at least 72 degrees F or better yet, get a heat mat to place the seed start trays on.

Your normal frost free date should be about the 20th of May. This means that the tomatoes and peppers should be potted up to at least 6 inch containers though 1 gallon would be a better choice IMO. Whatever container you decide on, make sure you calculate the maximum number you can put in the greenhouse without impacting your ability to get in and care for the plants. In other words, don't fill the greenhouse up so you can't get in.

Whatever you think you know about growing plants, get ready to revise it drastically. Growing in a greenhouse is very different from gardening in the summer season.

Why start peppers earlier? because hot peppers can be very slow to emerge and then they grow slowly and sweet peppers are similar but not as finicky.

Why not start earlier? Because the plants will be so large by the time May 20th rolls around that you won't be able to keep them in the greenhouse. A tomato plant at 12 weeks old will either be 3+ feet tall or else it will be severely stunted from growing in too small a container. You DON'T want stunted tomato plants, they rarely fully recover except with expert care.

Figure out what you are going to use for a grow mix. I would suggest getting a couple of 3.8 cubic ft bales of promix BX. That will give you a good baseline to determine where to go in the future. Get familiar with places like this one. You are going to need supplies and will either have to find a local supplier or else order them shipped in. http://www.mortonproducts.com/

Spiders are your friends. I get asked repeatedly how I control white flies. The answer is simple. As I walk through the house, I keep an eye out for spiders and move them to the plants. It only takes 5 or 6 hungry spiders in a small greenhouse to control virtually all the pesky bugs that want to suck on, eat on, lay eggs on your plants. My greenhouse is 23ft by 32ft so it takes about 50 spiders. I've been known to cultivate fruit flies just so I can turn them loose in the greenhouse to feed the spiders. Note that fruit flies will NOT harm seedlings but don't go there if you are trying to mature fruit!

If you try to overwinter plants, be sure to spray them thoroughly with neem starting about 2 weeks before you move them indoors and repeating every 5 days with a final spray just before you move the plants into the greenhouse. Why? Because the neem will help you avoid moving aphids into the greenhouse. Did I mention that the phrase "population explosion" was invented to describe aphids in a greenhouse?

The temperature you grow tomato seedlings at is important because it determines how productive the plants will be later in the garden. Start out maintaining temps above 60 degrees until the plants are at least 5 weeks old. Then you can drop the temps down as low as 35 degrees for 7 to 10 days. After the cold treatment, raise the temp back up to 60 degrees minimum until you set the plants into the garden. If you dig around on the net you will find a few descriptions of this process that tell how much more the plants produce as a result of the cold treatment. Please note that it is fine to keep the temp above 60 the entire time seedlings are in the greenhouse, you won't really lose anything, but if you choose to cold treat, you will increase the crop the plants produce.

Another trick you will need to know is that cold temps seriously slow down plant growth. Just one night at 35 degrees will inhibit growth for up to a week with temps at 70 degrees. There is a caveat to this. If your greenhouse goes down to 35 degrees in the night, you can completely reverse the growth suppression by letting the greenhouse go up to 100 degrees the next day. This is easy in direct sun, just set the vent to open at a higher temp. The maximum temp you should allow in the greenhouse is 120 degrees for seedlings. It won't hurt them as long as they have plenty of water.

I'm going to wrap this up by saying that the single biggest mistake you can make when growing seedlings is to overwater. Tomatoes and peppers should get to the point where they start to wilt before you give them water. This is another little trick to pull on the plant because it forces the plant into a phase where it puts most of its energy into expanding the root system trying to find more water. Guess what that enhanced root system does when you set the plant out in the garden?

Here are links to review.
http://www.kdcomm.net/~tomato/Tomato/start.html
http://www.selectedplants.com/seedlings.htm

DarJones

[Dawningstar1]

I live in Ontario, about two hours from the border lol... close to Niagara Wine Country lol...

Last year, I started my seeds on Jan 1st, and then kept them in my sunroom, something I don't have here lol, but I thought with the greenhouse I could start some this month and put them out in the greenhouse come March or April to get a boast on the season....

The greenhouse here I will post pics soon, it is still warm, and I swear if I had had a pool inside of it I could have swam inside up till first of Dec...

Ground is not froze here, and in the greenhouse even though the door is not secure and there is a gap where fan should be I can sit out there for hours in a sweater and not see my breath...

Even in the bad snow storm we were suppose to have we only ended up with about 6 inches.... I was out there in the greenhouse toasty warm...

I got to see this greenhouse before we moved here in the end of June and it was really hot inside and that was with the door open....

No way to heat it here unless I want to spend money on solar or generator lol as there is no hydro nearby....

[Fusion_power]

It does not matter how warm you are in the greenhouse. It matters how warm the plants are. A tomato plant MUST stay above 32 degrees to avoid freezing. If the greenhouse gets down to 32 degrees or less, you will lose plants. Even if it only goes down to 38 degrees, the plants will be severely slowed down for most varieties.

The temperature in a greenhouse in the daytime is one thing. The night time temp is something else entirely. You have to know the night temp to understand how wide the variation is between daytime when the sun is shining and night when all that captured heat seeps out and goes away.

While a sand floor is nice in some ways it does not hold much heat. A few black plastic barrels full of water will absorb heat in the day and release it at night moderating temperatures both day and night.

The best advice is to start some plants and get a good thermometer so you can monitor the temperature. Then you will start to find answers to your questions.

DarJones

[Worth1]

Are you saying you dont have electricity oil or gas to heat the house or place you live in???????

Worth

[Dawningstar1]

I got wood heat in house, best heat in the world, rest of house is electrical as if but by using wood hydro is only a $100 per month me like that lol but house is about 300 feet from greenhouse and the garage doesn't have hydro.... so we are slowly working towards solar or something lol...

[Dawningstar1]

Originally Posted by Fusion_power

It does not matter how warm you are in the greenhouse. It matters how warm the plants are. A tomato plant MUST stay above 32 degrees to avoid freezing. If the greenhouse gets down to 32 degrees or less, you will lose plants. Even if it only goes down to 38 degrees, the plants will be severely slowed down for most varieties.

The temperature in a greenhouse in the daytime is one thing. The night time temp is something else entirely. You have to know the night temp to understand how wide the variation is between daytime when the sun is shining and night when all that captured heat seeps out and goes away.

While a sand floor is nice in some ways it does not hold much heat. A few black plastic barrels full of water will absorb heat in the day and release it at night moderating temperatures both day and night.

The best advice is to start some plants and get a good thermometer so you can monitor the temperature. Then you will start to find answers to your questions.

DarJones

Sounds good to me, will the sun pentrate the white plastic to see the barrels if I get some, I could put a few storage containers of water in if that is the case.... just don't know how strong sun is here at this time of year lol...

[Stepheninky]

Probably the best thing if the space is not heated would be to start out with some colder growing crops like kale, lettuce, etc... and see how that does in the space. That way it does give you something to grow. See how that goes and monitor the temps inside then plan from there. I know we have growers that are in similar climates and in closer proximity to were you are that might be able to help with plant out times and such that may just be busy due to the holidays but I am sure a few more will chime in and help yea out.

Also the more details you can give us on the greenhouse or some indoor outdoor pics might help. For example a single layered plastic film covered green house with no heat at night usually gives about 4 degrees F of protection A green house that is double layered plastic film gives about 7 -10 degrees F protection. I guess the point I am trying to make is that what the green house is made of and how it is build will help others here to better help you as well.

[Dawningstar1]

thank you so much, I am really looking forward to seeing what all I can grow!!!

The person who lived here before me left a small garden of delights, he grew peanuts.... I roasted them but I think I didn't do it long enough as they still tasted like peas to me

[Stepheninky]

Originally Posted by Dawningstar1

Sounds good to me, will the sun pentrate the white plastic to see the barrels if I get some, I could put a few storage containers of water in if that is the case.... just don't know how strong sun is here at this time of year lol...

Its not really the sun shining on the water that matters its about thermal mass.
basically solar heat is generated during the daytime inside the greenhouse. By using stones, water, or other things that have a greater thermal mass than air, Basically the warm air transfers heat to the water barrels. Then at night as the air cools the warmer stones or water release that stored heat back out. Black absorbs heat energy. White reflects heat. So by painting the water barrels black they can absorb more heat during the day.

[Worth1]

Originally Posted by Stepheninky

Its not really the sun shining on the water that matters its about thermal mass.
basically solar heat is generated during the daytime inside the greenhouse. By using stones, water, or other things that have a greater thermal mass than air, Basically the warm air transfers heat to the water barrels. Then at night as the air cools the warmer stones or water release that stored heat back out. Black absorbs heat energy. White reflects heat. So by painting the water barrels black they can absorb more heat during the day.

Thats why snakes lay on the road and rocks at night in the desert, so they can soak up the residual heat.
If you can trap this residual heat from the day time inside the green house it will help keep it warm at night.

Worth

[Fusion_power]

Note that Worth trapped some residual heat from his hot peppers and they still set him off like a rocket leaving the launchpad.

Since you have wood heat in the house, consider putting a wood heater in the greenhouse too. I bought one used for $30 a few years ago and have used it extensively since then. The only problem I have is that it requires wood added about every 6 hours to maintain even heat. I've been getting up at 2:00 a.m. to "feed the baby" heater for so long that it has become part of my daily routine.

DarJones - who is on his way out to put more wood in the heater now.

[hill60]

Hi from the West Coast.

The advice you been given is right on target.

I have an unheated greenhouse that is used to extend my growing season. My tomatoes are grown in containers that can be moved in and out depending on the weather. You can get an extra six weeks at the start and then at the end of the growing season this way.

I thought about heating the greenhouse and decided against it because of the cost. I'm a wimp and don't have the dedication that Dar Jones does 2:00 a.m. just isn't going to happen.

Hill60

[Dawningstar1]

LMAO I will just skip past getting another wood heater, I might have to look for a new man if I pulled that Hubby says six more weeks of growing season is more than enough if it don't cost him more of a sore back

Right now I am trying to figure out how to start seeds no later than Feb.... so that when possible I can move the plants to greenhouse, now I am thinking of all the rocks around the yard and how many plastic containers of water I need to keep the greenhouse warm at night... thanks for great ideas I will keep you up date

picture of greenhouse