Zone 8a might be good for greenhouse fruit. But it will be tough if you're from the Southeast. So it would help to know your location and soil, texture and drainage.

This post was edited by fruitnut on Fri, Feb 28, 14 at 22:51

Texarkana is the location. Texas/Arkansas line. Drainage is good. I actually have several choices for locations which would affect drainage. My soil I think is a loam type but I will look to make sure. I would say medium textured.

The good news is you get pretty good chilling in that area. So you can grow quite a few things. The bad news is there is nothing you can do to get growing conditions that will resemble CA. It's just too hot and humid. A greenhouse can't reduce the heat or humidity. A high tunnel will be even hotter depending on setup.

I don't know much about fruit trees as I am a newbie but in the late winter fall early spring you can really reduce humidity in a greenhouse. I have messed with greenhouses as dad had around a half acre under glass. He could try very low chill varieties and then force them late winter early spring. The problem is how much are you willing to spend for the fruit? In the summer take the end walls out and you can maintain no more than a 10 deg differential in the heat without fans and that heat diff will help with humidity too. Or use one year film and take it off in the late spring early summer.... which would flush the ground of salts when it rains. Salts would be you worst enemy in a greenhouse if you grow in the ground.

With money anything is possible just not practical.

Just my 0.02 cents

kyyada is right, enough money and you can do anything. But central air conditioning is the only way you could make a greenhouse like CA in a Texarkana summer. There are many things you could do during the cooler half of the year.

What I'd concentrate on in that area to grow CA quality fruit is figs. They love the heat and will grow pretty well there without protection. But with a high tunnel/greenhouse you could have 6 months harvest of the best tasting fruit possible in that area.

It's the pluots and such that grow well in CA that probably aren't realistic in that area.

I'm still short on time this morning. More later if there are any questions.

Thanks for the replies. Looks like I might be out of luck. The Pluots are one of the most appealing to me. I am not a huge Fig fan but my grandmother made the best fig preserves ever.
Money is always an issue. So I will have to take that into consideration.

I guess the question to ask is would the inclusion of a green house allow me to grow some fruit normally impossible or hard to grow without breaking the bank or should I just work with what I have.

I don't want to create a monster to maintain but I would go to some extremes if I were not doomed to fail. Air conditioning is an option. Forcing would mean heating as well. I am guessing from what read.

Once the fruit was harvested would you have to still maintain certain temps and humidity or do you open the greenhouse up like kyyada mentions.

I am not selling the fruit. It will be for me to eat so it doesn't have to be perfect. Just reasonable.

Thinking out loud here but would growing these in containers make more sense. This way the soil is maintainable and the trees moveable.
The green house could be built in two parts where one part is conditioned and the other is say normal. As my weather gets rough I could move them back and forth.
Fruitnut is correct on our heat and humidity. It can be relentless. Last year was not bad. Three years before that we're rough.

BKG1:

Maybe you just haven't had good figs. I too thought they were yucky mush until I got away from the big watery ones and found some that dry down better as they ripen. Strawberry Verte is better than pluots IMO. Not better than the best apricots and nectarines.

Containers make sense because it keeps the trees smaller and is much more flexible. You don't need to put a tree in the prime location until it is ready to bloom. Then if you don't like it you can replace it with something else ready to fruit. That said in-ground is easier.

Perhaps I shouldn't be so negative on your greenhouse prospects for things like pluot and nectarine. If you build the greenhouse right you can probably make it work. That means a good evaporative cooling system (wet wall opposite exhaust fans), more than one air exchange per minute, a greenhouse covering that reduces heat input (something like Solar Ice or woven poly), and probably aluminet 40% shade cloth.

I won't try central air, too expensive, think a house times 10 electric bill on a sqft basis. A 200 sqft greenhouse might cost as much as a 2,000 sqft home. There are heat calculators that could figure that out for you at greenhouse megastore.

Pluot and nectarine will take high heat, in fact need it for best eating, 95F is OK, even 100.

Have you read my best writeup?

Here is a link that might be useful: greenhouse fruit production in west Texas

You should also strongly consider a high tunnel design. The difference from above being that it would be naturally ventillated during the frost free season. It would still be covered on top in summer to try to keep rain off fruit. But sides and ends fully open for ventillation. I'd cover all for birds and top with the 40% aluminet for heat. This would get you away from constant electric bills and fear of power failure during a heat wave.

A proper high tunnel design could be converted to evaporative cooling later on if needed. A high tunnel still needs to be very strongly build unless you want a big kite.

Don't get me wrong I like figs. They just were not at the top of my list.
Well that fig tree will find a place in my orchard. I appreciate the advice.

I think I have read most of your posts on both forums. Your greenhouse has me excited to think it might be possible. I have to admit. I don't know a whole lot yet about the dynamics of the greenhouse but I will start the research needed to ask better questions using your suggestions as my base line. Please bear with me as I get better at the concepts associated with greenhouses. Thanks for the link. I will start with reading your right up again. I think I have watched a thousand YouTube videos on fruit trees. I actually watched one where a lady was using a brix meter. I had no idea this type device existed. I came close to purchasing one but decided to wait. My tastes I think are more towards the tart side. It would be nice to use the meter to see. I have learned a lot since I first read your right up so this time should stick better.
I will check the Megastore out too along with the high tunnel design.

If anyone comes across any other reading relative to this please post and I will research them as well. Kind of like a sponge right now reading everyone's posts.
Thanks again.

There are some useful, easy to read writeups below.

Here is a link that might be useful: New England GH info

Quick thoughts on an example high tunnel for fruit in Texarkana. 20ft wide by 30-36ft long, enough for family of 4. 12-13ft peak and 6ft roll up sides. Potted trees 6-7ft tall. The top half of a high tunnel is solely to vent hot air. Bottom half is for the trees. Cover top with single layer woven poly and 30-40% aluminet year around. Ends open completely to the top in summer and possibly during winter chilling. Ends closed during frost danger. Sides and ends covered all year with bird netting for critter control.

You need minimum of 800 hrs in winter between 32-45F for chilling of low/medium chill fruits. You might need extra winter shade cloth to hold day time highs below 60F to aid chilling.

Minimum 70,000 BTU heater for spring frosts.

The structure would need to be built strong because it's a big kite when open like that. Main beams set in concrete and 2-3 inch tubing with bracing.

This post was edited by fruitnut on Sun, Mar 2, 14 at 21:13

Outstanding. I think you just designed my ideal green house.
Few questions. Does the bird netting size matter? I would like to use the really small size keeps out larger insects. The reason I ask is airflow considering our heat. How does the extra shade cloth work? I assume it would roll up so it could be used or not on demand. What types of heaters are used? Electric/duct style or does matter.
One last question. Did you purchase a kit for the greenhouse? I want to start pricing my options. My time line is up in the air without knowing costs. I want one now but my wife says not yet. Is there a perfect time to start the greenhouse up?
I read your write up. I have tons of questions but I think most can be answered by some research. I started going through some of the links but my son stole the iPad. Thanks again. I truly appreciate the help. I look forward to one day posting pictures of the greenhouse and the results.

I think the woven 30% black polypropylene would allow enough airflow. I know it's strong and lasts much longer than aluminet. It could be used over the whole thing. But like you I'm a little concerned about airflow.

An extra piece of 50-70% with taped edges and grommets could be pulled over top in winter very easily on temporary basis. It could also be used on those few hottest afternoons in summer when it hits 100F+. I won't buy this until you find it necessary.

I've got a Modine heater with electronic ignition that has been bullet proof. But that's like $900?? There are portable ones that use propane for a couple hundred. You'd probably only need it a few nights each spring.

Get your trees going and put it up before they start blooming. I'd start in fall and try to have it ready for those spring freezes.

I purchased the frame and added the equipment.

This post was edited by fruitnut on Sun, Mar 2, 14 at 22:28

Do you have some electronics involved in your control scheme of your greenhouse? Or do you manually control the heat and fans so forth?

Mine has an automatic controller. But a greenhouse with fans and heater could be run off about 3 thermostats. A high tunnel with only a heater could be manual.

Which controller do you use? I am an Electrical Engineer and I could design and build my controls. I could use a micro controller with cheap touch panel and design the interface and on off controls for the fans, heater so forth. May not be needed in my area since I will probably only need the heater in springs like one we have now. The rest of the time it would be somewhat open.

With a greenhouse the simpler the better, opt for simple but reliable controls. Redundancy is also a good thing to prevent crop loss. Two heaters two fans ect....also try to work in some very small louvered fans for controling humidity. Horizontal Fans are good to to keep air moving. Spend extra money and get a heater with a stainless steel heat exchanger the ones for shops and garages won't last long. One thing you will encounter is friends and family wanting to bring stuff in on you...you will make them mad but don't do it unless you love insects and diseases.....

kyyada,
It was like you were reading my mind. My good friend is in the heating and cooling business and I was considering the shop style. I had mentioned my greenhouse idea to my mom and the chain reaction you mention had already started.
Thanks for the advice.
I have started my research. Maybe I will have some good questions to ask once I get further down the road.

My controller is a Micro-Grow Gromate. It has three cooling stages, air circulation, and two heating. I only have one heater. My only compliant is that the cooling stages are locked together and separated by 2F. I'd rather the cooling stages were independent so that 2F wasn't locked in. But it has worked flawlessly for 9 yrs and I haven't had to calibrate temperature in yrs.

In both controller and greenhouse design the systems are set up for tomatoes. You start talking fruit trees and suppliers don't know squat. Some controllers are locked into ideal tomato temperatures and nothing else.

Number one key point is a greenhouse should be designed around the needs of the crop. Don't look for neat, energy saving, often expensive greenhouse features and try to fit the crop into that design. The later is what I often see when someone wants help.