" which would add the most produce for the space". A small greenhouse, with climate controls- heated and cooled- will produce more vegetables cost effectively than growing in a lighted, and heated, garage. Sun light/ heat is free.....

My cucumber, tomato, pepper ,herb, and ornamentals small greenhouse is used year around . The only down time is for the tomato/ cuc /pepper in July and August because of the high summer temps.

Not stated where either of you are but in mid Atlantic I prefer to just extend the season by a few months on either end of the growing season. I have no desire to keep growing from December thru February as it would be too costly and I prefer the vacation.

The comparison between outdoor crops and greenhouse crops is hard to make. My greenhouse tomatoes and peppers far outproduce outdoor counterparts. I can hardly believe the size and production of greenhouse plants, Some hot peper plants are currently over my head and loaded with fruit while most field grown peppers are 18-20" high and have moderate fruit loads. I don't use raised beds but cover soil with plastic and plant into soil. I figure one should be able to recover the greenhouse cost during the second month of sales.

which temperature controller you use?

Temperature control is complex in my structures because I believe that I alone can make the critical decisions. I have both two stage thermostats and separate one stage thermostats to control intake loggers and exhaust fans but I often override the thermostat controls by closing everything early in the evening to conserve heat and have switched additional fans. The entire exhaust fan ventilation system is shut down as days get warmer and I roll up sides as primary temperature control. I also rely on internal circulation fans to move air around and help to keep greenhouses uniformly warm or cool. The final feature is shade cloth to help cool inside temps on the hot summer days.

I have a greenhouse that I predominantly only use for non-summer months. Through the winter it grows greens (lettuce, spinach, beet, turnip, cabbage greens) under a floating cover with minimal added heat (old fashioned xmas lights on <30*). I haven't had anything die from cold... Read the Winter Harvest by Eliot Cole. if I'm doing a good job paying attention to it I can get oodles of greens in the space. (Hanging in baskets and grown in ground.). I've found that in ground survives the extreme cold much better than in baskets/pots. I've used water jugs as thermal mass and put a solar pool cover on my north wall as further insulation. I also start my earth boxes in the spring much earlier and can move them inside in the fall.

Having said that my outdoor garden far out produces my greenhouse for the summer. I don't use the greenhouse much in the summer since I don't have an adequate cooling system set up and I live in a high humidity (ie high fungus risk) area so misting system are risky... I did try tomatoes in and out of my greenhouse and those outside did 10x better (earlier and much more fruit).

However my regular garden is dead now (mostly) and I can still pick tomatoes/peppers from my still unheated greenhouse. Last winter I had fresh greens throughout and into the spring before my outdoor garden could yield.

Btw the #1 thing to increase your veggie yields in a garden or greenhouse imho is a quality drip hose and an irrigation timer (hose connecting is fine). Allows the garden to be watered without manual intervention (which I forget to do if work, family or travel distracts me).

Oh and you can buy lots of veggies for the price of a greenhouse so you have to make that choice because you love it...

We are in 8b and have a lot of 80-100' tall trees shading much of the yard. I place the greenhouse in the only place (side lawn) that gets morning and afternoon sun, blocked only for about 2 hours mid-day. It allows me to plant the vegetables earlier and most importantly, protect them from the squirrels, rabbits, crows, and deer that would be eating everything. This was the longest growing season in our 23 years here, I only took out the cucumbers last week, and picked the remaining small ones.

Currently there is only some Kale left, and the asparagus plants which I just cut back to the ground Saturday.

As a market gardener I look for the greatest return for the enclosed greenhouse space. Much literature will tell you that only flowers can give a better return followed by tomatoes. So I have chosen tomatoes as a primary crop to grow in my structures for many years. This year I dedicated one structure to peppers and it definitely paid great returns by having a marketable crop months early, and still ongoing.

I fault those who plant a crop in a greenhouse to get early yields only and then rip it out to restart another crop when the first crop is doing well and can continue to give good returns for many months. During December thru February I remove debris, clean, repair and renovate. The winter gap without plants helps to eliminate overwintering pests by eliminating a host on which they can survive. One can buy lettuce in stores over the winter for about the same as the cost of putting up with hastles of raising it indoors in our northern winters.

If I want to start tomato or pepper plants in greenhouse ground in March they are seeded indoors, starting as early as January. The cost of heating my house for my comfort is non-negotiable but the seedlings can get a "free ride" inside and a head start for the early growing season. The benefit of the greenhouse is that first flush of picking in May-June when others are just starting to think about gardening. If you can't get that then there is no real advantage to the greenhouse.

Melons and other vining crops just take up too much room but can be started a few weeks early for transplanting using a benchtop greenhouse. After starting, the transplants usually do Just as well outside under row covers. I will admit that I reserve space in my high tunnels for a row of slicing cucumbers. The return is good and they predominantly take up vertical space when netting is used. My main problem is that the Food Bank doesn't even want the glut of surplus cucumbers that the peak production supplies and 6 weeks later you wish you had a few extra to harvest. This year I gave up on a followup crop because Downey Mildew was in our area already. That is when I just plant a row outside and take my chances with less onverall investment.

I used to grow greenhouse basil for many years and may return to it if Basil Downey Mildew can be controlled. Most other herbs seem to do as well outside. I looked for a niche crop last year in My latest high tunnel and so I'm growing a few rows of primocane black raspberries. Still harvesting a few but they have turned into a briar jungle and I'm wondering if I could have utilised the space for a less demanding crop.

Hi there! I am in zone 5b also and I have a 8x9' 7 feet tall hoop house/ I call a greenhouse. It is very sturdy with multiple layers of plastic. I grow more sub tropical fruit trees/plants. bananas, grapefruit, papaya and so on. every spring (late Feb- early March) I do my seeds and they turn out excellent start producing edible Vegetables by early June. depending on the vegtable.

Greenhouses that are about that size can easily run from Mid April until Nov without heat. If allowed to heat they run all season. all winter greens do fine, beets and carrots. Currently my greenhouse is acting like zone 8. if I get heading cables I could possibly get it up to zone 9!

One more thing - placement of a greenhouse is most important. In the winter find the sunniest spot for the longest period f time.

I hope this helped

Matt

We predominatntly grew tomatoes in our 17 x 48' greenhouse, had 4 long rows of raised beds and planted about 250 tomato plants, all pruned to one main stem and strung up on string with plastic clips. Yield was amazing, and I think the only crop that could have been close, although taking up much field space(and a lot of people hours to weed) was sweet corn. We intermixed with some hot and sweet peppers and basil that grew like trees, overall amazing production and I personally loved working in the greenhouse - strap on a set of headphones with an ipod and good to go for a few hours pruning and stringing!