which warm season plants can be grown from seed and transplant well?
I know tomatoes and peppers do well
what about squash, cucumbers, okra ,egg plant, ect
oldokie, You can start seedlings of almost any vegetable, flower or herb from seed and transplant them if you want. With some of them, the results can be iffy but you still usually get enough plants transplanted to make it worth your while.
Squash, cucumbers, melons: With squash, cucumbers and melons of all kinds, I like to start them in paper cups (I use the little bathroom-sized cups, which I buy in bags of 600 or 700 at Sam's Club or CostCo) and then transplant the plants, paper cups and all, into the ground once the plant has developed its' first true leaf. The cups rot away pretty quickly, especially if you are in an area that has fairly wet spring weather. If you hold squash, cukes or melons in small containers, peat pellets, the cells in flats, etc. for very long at all, their root systems are too confined and the plants will suffer transplant shock more easily and their growth can stall for a long time after they are transplanted into the garden. If I sow seeds of squash, cukes or melons in flats at the start of one week, assuming I have them in a warm-enough environment for the seeds to sprout properly, I'll have the cotyledons sprouting within a few days, and the first leaf about a week after the seed was sowed. That's the point where I have to hurry up and get them into the ground fast because their roots grow quickly and the plants can become rootbound quickly.
Eggplant: Eggplant is really easy from seed sown in flats. Just remember that they are related to tomatoes and peppers and handle them the same way. There's no reason to rush eggplants or peppers into the garden as quickly as you would tomatoes, though, because they stall at cooler soil temperatures. Unless you are going to raised your eggplants underneath a lightweight floating row cover, it is hard to get them off to the same early start that you can achieve with tomatoes because the flea beetles will relentlessly devour the eggplant leaves. So, even though I generally start seeds of tomatoes,peppers and eggplants at the same time, the tomato plants will go into the ground a lot earlier since they tolerate cooler soil temps and air temps fairly well. I hold peppers and eggplants about 2-4 weeks longer in paper cups than I do tomato plants, which means I usually pot them up at least once from their starter flat of tiny paper cups to larger plastic cups or styrofoam cups.
Broccoli, cauliflower, brussels sprouts, collards, cabbage, etc.: I start all these from seeds in cups and transplant them into the ground once the soil temperatures/air temperatures are at the right level for them. Usually the broccoli and cabbage go into the ground when the young transplants are 3 to 5 weeks old and have roughly 3 to 5 true leaves. It can vary a lot, though, if the weather is misbehaving an staying too cold. Cauliflower and brussels sprouts do better for me as fall crops for a winter harvest than as winter crops for a spring harvest because often the spring weather warms up too fast, but sometimes I plant them in spring anyway. When I do, I like to start the seeds in late December or early January and get the cauliflower and brussels sprouts in the ground by the end of January. That's the only way I have any chance of getting them to mature a produce a harvest before the weather gets too hot for them down here in southern OK.
Okra transplants well when small. I like to sprout it in the greenhouse or indoors on the light shelf depending on what air temperatures are doing at seed-starting time, and then transplant the plants into the ground as soon as they have a true leaf or two. Since okra can be really finicky about sprouting in cool soils, I get better germination rates when I start them indoors on the lightshelf, with or without a heat mat, though they are faster with a heat mat.
Lettuce and collards sprout so well in cool soils and tolerate cold so well that I often direct-sow them in either the ground where they will grow, or into large unmovable containers outdoors if that is where I intend to grow them. You certainly don't have to start the seed indoors or in a greenhouse, but with lettuce, it can help to get them up and growing earlier than usual so they have a chance to produce a great harvest before the heat makes them bolt in late May or in June.
You can raise root crops like beets, turnips, carrots, etc. by sowing seeds in cups and transplanting them into the ground if you want, but you need to transplant them when they are really young since the carrots, for example, make most of the length of their growth in their early weeks and then spread out and fatten up as they get older. Holding them in flats too long and then transplanting them once they're already trying to rapidly grow in length can stunt their growth or give them bizarre shapes. There's no reason to start these in flats unless you just want to try it to see if you can do it, which is why I have tried it....mostly just to show those folks who say you cannot do it that indeed you can do it if you choose. In a very wet year when there is a chance that seed might rot in our clay soil before it can sprout, I will start more plants in flats and transplant them than I do in a more normal year.
Beans and southern peas can be started in flats and transplanted, but because they grow so fast, you need to put them in the ground just as soon as you see the first true leaf forming.
I cannot think of anything I haven't tried raising in the greenhouse at least long enough to get the seeds,tubers or corms to sprout, and then transplanting them into the ground, but that doesn't mean a person should or has to start those things inside. Peas and beans, for example. sprout and grow like mad when seed is sown directly in the ground, so there's no reason to raise them inside unless it is for a gardener to feed their need to be growing something....anything....in the greenhouse or indoors while waiting for the cool spring soil temperatures and air temperatures to warm up enough for the plants or seeds to go into the ground.
One reason it could be beneficial to the gardener to start something like beans or corn in plantable pots (peat pots, paper cups, etc.) and then transplant them into the ground might be if the weather was being exceptionally erratic with recurring cold nights keeping the ground too cool. When that happens, like it did last year, planting can be delayed to the point that it may be hard to get heat-sensitive plants to produce a harvest before the heat shuts them down. Broccoli is one vegetable where it pays off to start with transplants, but there usually isn't much advantage to raising corn from transplants, unless you have varmints that eat your corn seed before it can sprout if you plant it in the ground.
Some years I raise almost everything from seed started indoors on the light shelf or out in the greenhouse, and other years I only raise a few things, like peppers and tomatoes, from seed started indoors. It depends on the weather. In hotter, drier winters, I don't start much indoors from seed because I'll be able to direct-sow it earlier than usual in the ground.
I don't plant so much by the calendar but rather by soil and air temperatures, which can be highly variable here some years. I'm always aware of what sorts of days-to-maturity my various edible crops have, and I know about which week of the year we generally get too hot for those crops to perform well, so when cold temperatures hang around too late in spring, I will have almost everything started from seed and growing in the greenhouse so I can rush the plants into the ground as soon as the persistent late, cold temperatures stop being a problem. It's kinda a gamble, because these last few years, my garden has been hit by one or more killing frosts the first week in May. That sort of weather is very hard on plants like corn that generally can go into the ground in late March here in my part of the state. Last year, I planted as much on time as I could, and then covered up the corn plants with floating row cover when we had our late cold nights about once a week throughout April and into the first week in May. By the time we had our last frost/freeze here, I had corn plants that were over a foot tall and were becoming too tall to cover up. However, once the cold weather departed and I wasn't having to cover them up, the plants shot up tall fast and we had a really early corn harvest considering we still had freezing weather the first week in May. That's part of the risk with starting plants from seeds indoors or in a greenhouse---since they can get rootbound so quickly while in small containers, you have to put them into the ground sometimes even when the weather is still too cold for them.
We often to from "too cold" for tomato plants to be in the ground to "too hot" for them to flower and set fruit well down here in southern OK all in the same week, which can make it very difficult to get a great tomato harvest. (It is even harder for someone like Leslie in SW OK where the weather heats up really hot really fast.) Last year, I put 3' tall hoops over my rows of tomatoes and kept row cover over them for most of April and early May. When I finally removed the row cover around May 7th or so (relying on memory here), I had some tomato plants that were 3' tall and covered with small fruit...and that was just 2 or 3 days after our last freezing night/frosty morning. Without resorting to starting stuff indoors and covering it up as needed outdoors, I wouldn't get a good tomato or pepper harvest until late summer or early fall and that would drive me mad. I am cranky if I am not harvesting tomatoes in late April (from plants transplanted into large containers around the end of January thru mid-February) from container plants and by late May or early June from plants in the ground.
When I first started raising my own seedlings from seed, which I think was around the late 1980s, I only grew tomato and pepper plants from seed at first. Once I had that all figured out and knew what I was doing with them, then I added another veggie or two every year until I had mastered all of them. It was the same with flowers and herbs.
One way that I use starting plants from seeds in the greenhouse to my advantage is with succession crops. I like to use Pink Eye Purple Hull peas as a succession crop to replace one of the cool-season crops like broccoli, for example. So, when I think that the broccoli plants are about a week away from being done, I'll sow the Pink Eye Purple Hull pea seeds in paper cups placed in flats in my greenhouse. On the day I harvest the last bit of broccoli, I'll harvest it in the morning, yank out the plants and put them on the compost pile. Then I eat lunch, Then, in the afternoon, I'll work a little compost into the soil, maybe by hand or sometimes with my Mantis cultivator, and then I'll transplant the Purple Hull Pink Eye peas into the ground, planting them right in the ground in their little paper cups, and immediately watering them in. To lessen the likelihood of having them set back by transplant shock, I've already either cut a big X in the bottom of the cups or cut the bottoms off the cups so the roots can immediately grow down into the ground. Usually at the time I do this, the purple hull pink eye pea plants are maybe 2 or 3" tall. The raised bed that was full of mature broccoli plants at sunset will be full of southern pea plants by sunset. It used to freak out my garden friends to drive by and see broccoli plants in the morning and then to drive by in a day or two and notice young pea plants. They kinda thought it was magic. I told them, no, it wasn't magic....just a gardener obsessed with getting the maximum productivity from the ground, and that having replacement transplants ready to go into the ground on the same day I pull the old plants out means I get a harvest from the new plants maybe 10 days earlier than I would have if I sowed the seed of the new plants directly into the ground. Some years I relentlessly and obsessively have flats of new plants just waiting, waiting, waiting to go into the ground as succession crops, and other days I direct sow all the succession crops. It just depends on how busy I am with non-gardening activities at any given time.
The key to getting anything to transplant well is to transplant while still small so the plants aren't rootbound, to water them in well and to avoid planting anything while the soil temperatures are too cool for them. If you put warm season transplants into the ground while the soil is cooler than they like, they won't grow until it warms up, so you aren't gaining anything with putting them in cool ground. The most important thing, of course, is to make sure they are hardened off to outdoors air temperatures and wind. If you take very tender young transplants that have been totally sheltered from the wind and the sunlight, they usually die within a day or two of being transplanted. Hardening off is imperative.\
My greenhouse in late winter and spring looks like a crazy jumble of plants in all stages and sizes...to an outside observer....but when I look at them, I know from experience exactly which flat of plants has been hardened off and is ready to go into the ground tomorrow or the next day or the next week, and I know which ones need more exposure to sunlight and wind before they go into the ground, and I know which ones are a long way from being ready to go into the ground. I don't have to follow written plans or schedules because it is all in my head, but it has taken me a long time to get to that point, and I made lots of mis-steps along the way. Experience is a great teacher in that respect.
Since you are such an experienced gardener, all you really have to do is think about what dates you normally put your seeds in the ground, and then count backwards from that to decide when to start your seeds indoors or in the greenhouse. I allow 6-8 weeks for tomato plants from seed, but 10-12 for peppers and eggplants. I start them all at the same time, but tomato plants can go into the ground once the soil temperatures are staying at or above 55 degrees and the air temperatures are staying above freezing, whereas I'll hold the pepper and eggplant transplants indoors another 2 weeks to a month since they stall in cooler weather.
I have a friend who still is gardening at the young age of 91 (in my mind he'll never be old), and he always plants everything before I do because he is up on a higher ridge and I'm down lower in a creek hollow. If I were to plant when he does, my plants will freeze and die on a night when his won't because I have a colder microclimate. I can make up for my later planting dates by starting seeds in paper cups and transplanting them into the ground. When I do that with bush beans, I usually get a harvest about the same time he does, even though he often sows seed in the ground two weeks before I can transplant my bean plants into the ground. It kinda drives him crazy because he likes to have bragging rights for the first harvest, so I usually won't even tell him my plants have caught up with his. You have to do what works with your soil and your microclimate. When I first start raising seedlings indoors, I kept starting them too early, but it was because I couldn't predict how long the weather would stay too cold for me to transplant them. Nowadays, I use floating row cover to keep the young plants and soil warmer, so I can pretty much plant when I want to, within reason, as long as I am using the row cover. I've tried planting seeds in cups later, but it just doesn't work for me. The minute Fred tells me he just sowed his corn seed and bean seed in the ground, I feel compelled to sow mine into cups so my plants can catch up with his once I get them transplanted into the ground.
I'm sorry this is so long. I feel like I just wrote a book, but I wanted to cover it fairly deeply since it is a long, complicated topic. Beginning in early January, I am starting something from seed indoors or in the greenhouse virtually every week.
Thank you very much for your help
You should write a gardening book and I am not being a smarty butt. I don't know if there is any money in it though.
Helen, lol lol lol Thanks for the compliment though.
I don't know if I could sit still long enough to write a book. I love to read, but still find it hard enough to have enough time to sit and read a book, much less write one.
I doubt there is much money in writing garden books nowadays unless a person is an established garden writer with a proven track record of writing successful gardening books---someone like Barbara Pleasant, for example. (She rocks! I love all her books and magazine articles.) I'll buy any book written by Barbara Pleasant, Greg Grant or Rosalind Creasy, but I'm a garden book maniac. There's just so much info available online nowadays that I kind of wonder if garden books sell all that well any more in general.
Dawn, you are just a fount of wisdom for gardeners. No need for a book, just keep being generous with your knowledge here!