I hate starting seedlings indoors, but alas, this winter has held on so long that I was desperate to get my tomatoes and peppers started. So I did, inside. Now the days are warm enough for them to be out, I'm putting them outside during the day. But I think they are too leggy and the wind light breeze has knocked some over.
What do you guys do to harden off seedlings to prepare them for the big wide world that is the garden?
Up pot your tomatoes to a bigger pot. Bury them deeper, strip off the bottom couple of leaves if needed. They will produce roots all along the buried stem and it will make for a better plant.
I start mine indoors early usually and plan on going from starter flat to recycled cup (I thank the church ladies with bake sale donations in return for them saving their plastic and foam cups after coffee time after service) to trade quart to probably trade gallon before they go out. Then I harden off for a few weeks and I plant them by burying them deeper again, stripping off the bottom few leaves. (12-16 weeks for me to go from starter to out) Some of my biggest beefsteak types (brandywine, big zac, mexico, etc) will probably be in 2-3 trade gallon by the time they go out. Also when dealing with your starts in the house, put a small fan on them once they're a few inches high, GENTLE breeze to ruffle them. It's like an aerobics workout (watch out for drying out) and will make a stockier sturdier plant. I sometimes use a mild preparation of compost tea (maybe half strength) at 10-12 weeks or at the last uppot, plant is not dry and give them a half ration of the tea versus what they normally get for water.
Roots roots roots is the name of the game, and you can un-leg a tomato plant start by up-potting it into a deeper pot and burying it deeper. Tomatoes don't mind a mild root disturb unlike a lot of other plants... if you do an up-pot it should be two weeks before you put the plant in the ground or such for the season. Any sooner, skip and just go directly to planting in ground.
I put them out for the day for about a week, under a leafed tree or 30% shade cloth equivalent, in a wind protected area of the yard. Second week they get some of the wind and sun protection removed and stay out day and night (I pay attention to how cold it's getting, I try to keep them outside if it's upper 40's F, and keep them wind protected at night. You can sort of bunch them together to help prevent the wind from blowing them over, and just plant them deeply when you can put them in the ground. Good Luck.
Location: Cache Valley, zone 4b, Irrigated, 9" rain in badlands.
posted 2 years ago
I used to have a dickens on a time hardening off tomatoes. That was before I discovered the benefits of plastic... An 8 mil sheet of plastic as a canopy over the plants (so that they are open to airflow and don't overheat), will filter out enough UV light that the plants don't get sunburned. About 5 days of that, and they are ready for the garden, or for direct sunlight. I don't care if they get hardened off to wind... I generally don't have much wind at my place unless it's a gale. All bets are off if we have a storm like that!
My greenhouse has plastic glazing panels, so I can take plants directly from inside to the greenhouse, and then to outside a week later without worrying about sunburn. If weather is warm, I open the greenhouse in order to lower humidity, and allow wind in. A close collaborator runs her hands over the plants, caressing them a few times a day, in order to encourage stockiness.
I've been known to roll up a tomato vine like a spiral when potting it up!
I've never had this challenge before because my tomatoes never got this big before the weather was warm enough for them to harden off. Today was the first day they could be outside and I think they hate me. Sunburn and windblown. So sad. I'm so ashamed.
The official last frost day is tomorrow and the soil is just about warm enough to put them in the ground. I bury them deep so that they only have two leaves sticking out of the ground. They seem to love this. I might put them in early and cover them with a row cover and hoops. I'm not good with plants in pots. I want them in the ground ASAP.
You GO! Tomatoes are forgiving and for cherries I end up with at least 8" and more like 12" of root from base of seedling plant to top of soil when I plant out, for big beefsteaks All I Can Get, and Romas and Sauces and smaller (4-12 oz) anything over 12" is a bonus.
The next phase is to make sure as your vines grow, to give them adequate support and to pick out the bottom 12-18" (30-40cm) leaves and suckers as the plant grows. By the time a beefsteak is 3-4 feet tall (a meter approximately or a little more) I have that plant cleaned out at the bottom better than a foot to allow airflow, help keep insects from harboring, and overall set that plant up for 'greatness or growing'.
I grew competition tomatoes, hand pollenated for keeping the genetics known (some have 8 or more verified generations) and up to about 3 to 4 feet, the rearing of the plant is the same whether you want to 'grow for greatness' or 'grow for production'. It's at that point, when you have the plant well rooted, staked, trellised, or caged (depending on variety) and the whole thing trained, cleaned out at the bottom, and ready to go, what fate it will meet. Whether it is to fill your table and pantry or bend the scale, that much is the same.
I am at altitude, like Joseph Lofthouse, though he is a few zones warmer and a few thousand feet higher elevation... and UV is an issue. Almost any plant during the 'hardening off' appreciates a layer of 4 mil or heavier plastic, or shade cloth at 30% or equivalent tree shade for the transition. As I said, I plan on an indoor start, three pottings, and putting out huge plants according to when the frost date is. In my 6b, I have gotten RIPE fruit before beginning of July but that took serious work which you're not ready or able to do. No problem.
If in doubt, up pot your tomato seedling to remove any 'legging' issues, use windblocking of the grow area, and keep your hope up!