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glaswegian_gw

Hardening Off Plants?????

glaswegian
16 years ago

So around what time of the year will be best to "harden off" in southwestern ontario, with a last frost date of May 24?

So it's just a matter of taking the plants out when going to work in the morning, an dthen back into the house in the evening?

Comments (5)

  • wyndyacre
    16 years ago

    With an eye on the weather, you could begin to harden off plants around the beginning of May.

    This process could take a week or two of slowly exposing the plants to the elements. Remember that you are exposing them to *all* the elements....wind,rain,temperatures as well as the sun. You need to place them in a shaded, protected spot for a few hours each day, slowly increasing the time and then move them into more exposed locations also where they will get some breezes, higher temps, more sun etc.

    Wind can really destroy a tender new plant just as quickly as the sun can. I harden off my young vegetable plants but still protect them when I plant out with 3 qt nursery pots I cut the bottoms out of. I place the resulting "tube" around each tomato, pepper, broccoli, melon plant etc which allows some sun, wind and rain in but protects it from the worst of the wind. I remove them after a couple of weeks. They actually help the plant grow faster because they create a warm microclimate but they don't get too hot because they are totally open at the top.

    Make sure they are well watered when you begin the hardening off process-a well hydrated plant can withstand more stress than one already hurting for lack of water.

    Leaving them outside for a whole day, right off the bat while you're at work would probably be too much at the beginning. Unless you had an open porch that would provide shade and protection from the wind and knew that the temperatures wouldn't drop suddenly while you were away.
    Better to start out with say, a few hours in the morning and work your way up to 8-10 hours and then with milder weather leave out all night too.
    Someone on the Starting from Seed forum mentioned leaving them in the garage with the door open. That would be a good idea if they were back far enough from the sun and wind at first....and if you live in a neighbourhood where you could leave the door open while you're gone all day. :)

  • glaswegian
    Original Author
    16 years ago

    Thanks for that Wyndy! I guess it's better for me then to just do it on weekends when I can keep my eyes on it, and then after the 1st 2 weekends in May, I can then start to leave them on the front covered porch for 8-10hrs?

    I have a few to harden off, and I might just leave the rest in the garage on warm days, but without the door open. My neighbourhood is safe, but am not that stupid to risk that :-)

    I didn't realize there was more to starting plants indoors :-) God help me

  • glen3a
    16 years ago

    I have started hardening off plants just by putting outside on nice days, starting mid April to late April. That doesn't mean I put them outside every day, just the nice ones with maybe highs of 14C or higher, sunny, lighter wind.

    At first, give total shade, then perhaps an hour or two of gentle morning sun, or even when you come home from work put them outside for an hour or two of late day sun just before sun set. Then you work your way up. Often you'll find the older leaves may sunburn a bit but the new growth will be healthy. Once the plants can be in the sun 4 to 6 hours they will take more without any problem.

    Then again, it depends on where the plants are grown indoors. I've had plants that make the transition from outside to sun outdoors very well because they were grown under plant lights indoors and were very sturdy. Ones that were grown on a bright but not sunny windowsill indoors took more time to adjust, but that's the beauty of a north deck, you can put outside in bright shade at first.

    Also, if you start plants like marigolds which really don't need much head start time, you may be able to put them outside (at least on a regular basis) right from when they are just emerging from the soil, meaning they will be used to the better light conditions right away, and perhaps only have to be inside on poor weather days. You can also buy a mini-greenhouse, sort of like a small cold frame, which will allow your plants to be outside in cooler but sunny weather.

    Glen

  • runningtrails
    15 years ago

    I will have a lot of veggies to harden off this spring. I have a large covered veranda and I work all day M-F. Can I put them, covered, in the shade on the veranda from day one and just leave them there during the day. I can put them in the sun for an couple of hours after work each day and extend that on the weekends.

    Will that work? How early can they go out there, if covered to protect from frost. They wouldn't need to go out until mid May. They're not brassicas or other cold hardy veggies.

    They're growing on a south windowsill, no supplemental lighting.

  • sharont
    15 years ago

    To the last post:
    Watered well and out of the wind, I'd say your on the right track. If out of direct sunlight, the cover on should be OK otherwise they'd cook. Indirect lighting is good for a week or so then a few hours of sunlight a day. May 1st is a good stating date but bring them indoors at 7 pm. Day temperatures should be around 10 degrees C or higher, I should guess. Around the 14th you you could leave them out all night if no frost warning.

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