I am using a cold frame for the first time this year in southern Wisconsin. Currently I have lettuce and broccoli seedlings that I'll be planting out on Thursday. I'm guessing western PA and southern WI have some similar March and April weather, here's what I've found thus far with mine. They warm up very fast on sunny days, even a sunny day in the 30s. One day in March it was sunny and 35F, I didn't have plants in the cold frame yet and left it closed, it got up to 95F. My cold frame has an auto-venting arm that will open the lid when it warms up so the plants don't fry (they are adjustable, I have mine opening around 70F). Mine is on the deck (not on soil) so it does not retain heat very much. I kept 1/2 gallon milk jugs and filled them with bleach water. The water absorbs sun during the day and warms and then releases the heat at night. I also built a polystyrene cover for it for added insulation at night. If the previous day was sunny, my cold frame stays about 10F above the outside temp. If it was not sunny, it's more like 4-5F. I have tomato and pepper seedlings that won't tolerate cold, so I'm going to be putting them in the cold frame during the day and bringing them inside at night until the cold frame is staying above 50F at night. Given melons and pumpkins like warm, you might want to try that with those for a while. Good luck.

Okay, I have been experimenting with this for years. I'm way south of you, but I live on a mountain side, so I have mostly cool weather all summer (about a week of temps approaching 90 in the day, a month of 80s in the day, nights always in the 50s and 60s, 40s in May and September). Normally, for warm season crops, I plant the shortest DtM (days to maturity) varieties--tomatoes, squash, pumpkins, corn (rare, I hate to fight the raccoons), etc. I no longer even try melons, and have no interest in cowpeas or okra. :-) But you are asking about cool season crops. Yup, that's the majority of my garden, as the long, cool autumn before a hard freeze makes the cool season crops a joy. First of all, lettuce, radishes and spinach planted in the spring are going to bolt around mid-summer, even in a cool summer. It's a day-length thing, not temperature, for the most part. A few lettuce varieties have been bred/selected to hold longer before bolting, but I haven't seen great holding in spinach. Plan to plant again after the summer solstice. However, things will not grow as fast as the summer is winding down as they do when it is winding up. I have struggled with counting back 60 days from first frost to plant my 60 dtm lettuce or spinach and it just never matures. While you are learning the best practices for your area, I suggest you plant maybe 4 feet of seeds every 2 weeks up until you reach that (for example) 60 days before first frost. Keep note of it (I don't have a garden notebook, bad gardener, but I write this stuff on my wall calendar and have a stash of old calendars on top of my fridge) and you'll have a better idea of the planting window next year. Swiss chard and perpetual spinach are good spinach substitutes for mid summer. Both of these are basically beets selected for stems (chard) and leaves (perpetual spinach). I'm not a big fan of the stems, so I grow beets for a version of perpetual spinach. I rarely harvest the roots, but we do eat the greens. They also hold well into the cool season. If you like beet roots, plant again after sumer solstice to have nice tender roots at harvest time in the fall. Mulch thickly and you should be able to harvest the roots up until your soil freezes (or you can harvest and hold in a root cellar or your fridge). Turnips are also good for greens and the roots hold well in the ground until hard freeze. Again, plant after summer solstice. Winter radishes also go in after solstice. These are the Daikon radishes, but also Spanish black, German beer radishes, etc. These tend to be harvested much larger than spring radishes, and the ones I have grown are quite mild in the fall. Covered with mulch, they keep well in the garden until the ground freezes, and can be kept in a root cellar or refrigerator. My solution for cabbage and carrots is just the opposite of my warm-season veggies. I grow the long-season varieties! We like big fat carrots, so that works well. I don't rush to put them in early, but they can go in before my summer planting weekend (usually Memorial Day weekend or the weekend before). I've never had success with the early cabbages, but we've had some memorable January King cabbages that were just fine cooked, shredded for cole slaw, or shredded for sauerkraut. And again, they hold well in the garden until hard freeze. Oh, and we are a family that goes against the norm, even my kids like Brussels Sprouts (harvested after a frost and roasted, not boiled), so we have also grown those for late harvest. I have a nine-pack of Falstalf to go in next weekend, in fact. Need I say kale gets the same treatment as these other cabbage-family crops? I've tried Napa cabbage a couple of times without success. I'll have to take my own advice this year and plant a few every couple of weeks after summer solstice. BTW, deer LOVE, LOVE, LOVE members of the cabbage family. Rabbits do, too. I am learning to love rabbit fence (which keeps old fat chickens out of the garden, too) and re-mesh cages. Good luck with your cool-season garden! Catherine Here is a link that might be useful: Baker Creek's Radishes, many winter

Look, I started this thread because I wanted some advice about a particular structure that I seen in a Farmtek catalog. AT THE TIME, I wasnt thinking about actually purchasing equipment labeled as "cold frame equipment", or any other thing else that can be used permanantly and for several years. I had my eye on a particular structure that can be disassembled annually. I wanted to use this in an area of my property that I have used for hardening off. However, after talking with several people here, who have enlightened me here, I have seen where I can spend just a few more bucks and get a more permanant structure, and POSSIBLY learn how to do it myself. Okay---INSTANTLY, my brain went into overdrive. I HAD NOT PLANNED ON DOING THIS SO EARLY. When the time came for me to build any permanant structure, it was going to require tearing down a rather large dilapetated shed, building a large greenhouse, and rebuilding another shed. A very daunting task that we are not ready for yet. I never planned on having any kind of gh/coldframe this soon. Now, I am planning on building this on a separate part of my property. And since I have made this decision, I am all excited with nervous energy about every detail. When I started this, I wasnt thinking "cold frame",and I can guarantee that because,in my neck of the woods, no one refers to as it as a cold frame. It is simply "an unheated greenhouse". Mentioning the word cold frame around here is referring to those flat boxes with windows on top, barely 3 foot above ground. Once I understood what you all were explaining to me, I then realized that we all were talking about the same thing, and yes there are other posts about cold frames, but I did not START this one with the same thing in mind. Cactusfrak, first off, I swear I had no idea that you were a woman, none of what I said about "average women" is directed at you. Okay, maybe where you are from, a large number of women are skilled at carpentry, but around here there are NOT. I swear I did not mean to offend, I was simply trying to explain myself, and make it clear that I am the average woman. Cactusfreak, second of all, I am VERY sorry that I made you feel like people are attacking you via email. I SWEAR TO YOU THAT IS NOT HAPPENEING. Though, I can see why you would feel that way by my stupid "thank you for the private emails". I swear, I wrote that as a sincere thank you for those who took the time to let me get to know them better (rather than typing out all personal information on the thread). Cactusfreak, no one is attacking you, I was defending myself against what you said ON MY THREAD about how you feel about a few things. How could you not expect me to get my own feelings hurt? I have read your name on dozens and dozens of posts with basic questions, and never once did you feel the need to say that you dont feel you should give out information anymore because you have invested years into your research. You even shared a story about a woman who will not tell anyone anything, they must "pay her" for her hard work and years of research. You never shared such a thing before, yet you did it one MY POST. And I was supposed to just take that with a grain of salt? PLEASE REREAD what you wrote, and try to veiw it differently. Have you ever said such things to anyone else before? Will have to finish in 30 minutes..........

When there's a chance of frost I cover mine. Cool temps are great for the spinach, lettuce, brocolli ect I have two cold frames made of hay bales... gonna have to improve on 'em next year. Good luck