I have (have had) cold frame. It is not for planting in it, but to shelter plants in pots in it and germinate seeds, house seedling temporarily.

For tomatoes, you cannot grow in CF. Because it can get too hot during the day and too cold at night. The reason is that it it too low. The front height is about 16" and the back 32". Mine is 6ft long.

I am using mine right now to harden off some of my tomatoes. The 24 hour outdoor temperatures are in 40F(night low) to 60F( day high). So at night it wont get as cold as outside but still wont be warm enough for promote growth. So the plans get used to cooler night temps and after a while I take them out, and plant them. Then I might use mini hoops or things like W.O.W for a while until temperatures improve.

After that I use my CF for pepper plants in similar fashion. Also germinate cucumbers, chard, lettuce, ..etc.

If you really want to grow tomatoes in, You would need a greenhouse.

Seysonn

Where I am in Miami, Florida, I am wondering if a shade house would help tomatoes help tomatoes survive a Miami summer. I believe they are used mostly to help Orchids survive in sunny yards.

Yeah , I think a shade house should be helpful in Miamif and elsewhere in the deep south. Structure can be like a green house, with screen and shade cloth combination, designed to get just the right amount of direct sun light.

Seysonn

When in Italy a couple years ago, I noticed acres of plants protected with shade cloth. It was miserably hot and sunny. Seemed like the Italians solved that problem.

Keski

Talking about cold frame ( I have no high heat problem) , I have been making the most use of my CF this season. When I give my seedling sun and fresh air (as part of hardening off) I put them in the CF at nights. Inside the CF is slightly warmer at nights than being outside.
Once I am finished with the tomatoes then the peppers are going to go in the CF during hardening off. It is a very useful thing. You can even germinate other thongs like squash, cukes, beans , basil ..etc.

Sey

I use mine for hardening off: protection from the wind

Wouldn't a cold frame arrangement help raise the early soil temperature past the critical point? Just use it for appropriate non-tomato plants and move it out of the way when the toms are demanding to go into the ground? (caution: even though I do all germination outside, I haven't used a CF since they were made of wood and glass storm windows because plastic wasn't invented yet.) I know there's a scale problem but early toms are worth it!

"Where I am in Miami, Florida, I am wondering if a shade house would ... help tomatoes survive a Miami summer. I believe they are used
mostly to help Orchids survive in sunny yards."

My parents' home in WPB had a grapefruit, an old-timey avocado, and an impossibly huge ficus tree. They held what seemed like a hundred orchids and bromeliads 24/7/365. It would seem you guys have an ideal orchid climate.

I'm not familiar with midwest weather Randy but in North Tx I must plant at the very earliest date after frost,plant two weeks early and cover when frost threatens or use cold frames to give plants a head start. The time between last frost and 90 deg F where blossoms no longer set isn't long enough for tomatoes varietes over 70 days. Most people plant two weeks before last frost and cover as needed. The problem with that is if you are delayed in removing covers plants can be shocked or killed from overheating. My answer is in my cold frames. My frames are much taller than conventional. I am both curious and frugal so I repurpous,recycle and experiment at every opertunity. I will explain one frame that you are familiar with so that you can see how I build a frame from scratch. i rescued a supermarket reach in dairy case which is about perfect. I cut a 6" vent near bottom and installed a 3" flexiable hose at top. Hose runs down 18"to connect to a box containing fan from dairy case. The descending hose prevents heat lose by natural convection (warm air rises,cold air drops.) The thermostat has one set of contacts that make on temperature rise above an adjustible 32F to 55F and break as temperature drops which in turn control cooling compressor. There is a secound set of contacts which make and break inverse to first set. When unnessary components were stripped,I retained defrost heaters and connected them to the secound set of contacts which make on temp fall turning heaters on then break when temp reaches 45-50F. Another salvaged t-stat was mounted high in case, internally altered to perform in the 80F range and connected to fan. I save and raid gas station island trash for black oil,trans fluid and anti-freeze jugs. Jugs are filled with weak mix of water/anti-freeze then placed inside case where solar heat is stored then released during night to miniumize energy used by defrost heaters. A chime is connected parallel with heaters and a buzzer with fan to allow me to dial them in. Plants sit near top in colder weather then decend to lower shelves as they grow and weather milds. When plants are removed from flats they go into 1 gallon pots. Cumulativly, years tinkering has shown as cu ft space inside frame increases, maintaining temperature becomes increasingly easier. Gallon pots ease moisture and nutrient maintainance, reduce transplant shock and alow plants to hit the ground running. I hope this was relivant to your question.