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andreap_gw

help! 'ws'? seedlings and predicted temps (longish)

andreap
15 years ago

HI, Durham, NC gardener here, sorry to have been lurking so long. I started some seeds in six-pack cell pots and coir soil that germinated in my mini-greenhouse on the deck in a little over a week, after a few days days of cool rain and then 70s day temps. Now I'm worried they won't survive the predicted 32 degrees tomorrow night. I had them in punctured plastic domes, inside my mini greenhouse, whose covers are torn, so they do not retain all the heat they should. But I did put black plastic and a jug of water in the bottom of one of them to retain heat. Do you think I should bring in sprouted: petunias,

strawflowers, rudbeckia (cherry brandy), gomphrena.

The seedlings are very tiny. I am amazed they germinated at all so soon and am afraid of losing them, but do not have space with adequate light for them in the next couple of days until spring sun returns. I have germinated walla-walla onions [not very happy] and monopsis indoors and have to bring them back in for our next cold spell and the only lamp I have (not to mention my numerous houseplants that need some light). My tomatoes and peppers are still out there in another mini greenhouse without germination. I hope they do not grow mold until they germinate! I did water with a mild hydrogen peroxide solution. This is my winter sowing method, because if I do it 'their' way it is too hot here at the crucial germination times or in between if I keep them covered in a jug or anything else. So what would you do with so-called tender seedlings with our crazy weather? Can I let them tough it out?

Times are tough for all of us. I can't afford to buy any more plants or seeds right now. This is maybe my last year of annual and veggie gardening. I may let my perennial herbs and wildflowers take over.

Thanks for any advice. I have a lot to give away but don't go to swaps.

I really respect and love the winter-sowing forum but it really hasn't worked for me with these crazy fluctuations in temps here, at least where I live. How do y'all do it? And what do you do now? Hey, at least 'we got spring'! Thanks to all of you for the inspiration and advice I've been reading here for many moons (and Happy Spring Equinox)!

Comments (7)

  • pfmastin
    15 years ago

    I don't do any winter sowing, so I can't help with that part. I'm sure someone will be able to give you some good advice. In the meantime, can you bring them in a garage or outbuilding for the night? It looks like it will be getting into the mid 50's in the day time where you are. This time of year, it seems like I spend half my life hauling plants in and out. :) In my experience, peppers and tomatoes need warm soil to germinate. I use seedling heat mats for them. Hope this helps.

    Pam

  • drippy
    15 years ago

    Hi - I'm a future (hopefully not too distant - my DH has been working in SC a year while I've been in New England trying to sell the house) Carolinian, and I hope I can help.

    With WS, you will have better success if you ditch the mini-greenhouses (we're talking about those flats that hold 12 six-packs, right?) and go to deeper containers. A lot of folks use milk jugs or 2-liter soda bottles - I use, for uniformity, containers that are about the size of 1 lb. margarine containers. I purchase them in lots of 50 from a restaurant supply store. However, there's no need to purchase containers - you can use margarine containers, provided you cut out the center of a lid that doesn't let light through and replace it with plastic wrap. The clear containers I buy salad greens in work well, too. The key issue is soil depth - the 6-packs just aren't deep enough to sustain the seeds once they sprout.

    While you are still getting nights below freezing, you want to leave your containers with their covers on. You can gradually open the holes in the top to start hardening off if you want. I'm considerably north of you, in a zone 6b - I have some sprouts, but I've left the lids exactly as they are; haven't widened the holes at all. We are still getting hard freezes up here, but I haven't lost any sprouts yet.

    What I do not have, that you do, is 70 degree days. If I were there, I would look to keep my containers in a moderately shady location, still keeping covers on, and watch the moisture level, too. If your temps get to mid-70s or higher, I'd think about widening the transpiration holes, even if you are still getting freezes at night. If your temperature variations are really extreme, uncover your containers, and cover them (use towels/sheets/remay if necessary) at night - WS veterans repeatedly say they lose more plants to heat than to cold.

    I hope that's somewhat helpful. I'll be moving to the Greenville/Spartanburg area of SC when I get there. It's only one full zone warmer than where I am now, and I am confident I'll be able to adapt my WS techniques to the location.

    And oh yeah, happy Equinox to you too - this winter was the worst I can remember in a long time here, and I am soooooo ready to be a Carolinian!

  • denni-oof
    15 years ago

    I'm new to ws'ing too and am wonderging the same thing. I live in the western part of the state. I've decided to bring mine in for the night and carry back out during the day. So far only about eight of my 21 jugs have sprouts, so I'll bring those eight in and the others should be fine. I know it's a hassle lugging stuff in and out, but it's only for a night or two, and I'm not taking any chances.

    denni-oof

  • mommyto2
    15 years ago

    Hi guys!!!
    Andreap, I also live in Durham NC and have been sowing seeds in my little plastic greenhouse for 2 years now. If you are worried about your rudbeckias don't be, I had my cherry brandy germinate before we had the week of night time temperature in the teens and all I did was cover them with some old towels and they made it out just fine. The other annuals I can't say since I haven't grown them myself, but since it's not a deep freeze, I wouldn't worry about them too much. Just cover them with an old blanket and they'll more than likely be fine.

    I have also started winter sowing in milk jugs and now have zinnias and other tender plants just sprouting. I'm just going to cover them with some plastic or a blanket and hope that they make it. I will be crazy to drag them in and out for two days. I already have my carport full of plants that I'm going to bring indoors tonight (tropical plants) and that's just too much work.
    I have my milk jugs in semi shade which helps if you're worried about the temperature swings.

    I hope my advice helps you. It's nice to see someone who lives and gardens in the same city I do.

    Monica

  • trianglejohn
    15 years ago

    In my experience the only two you should worry about are the Gomphrena and the Petunia. I wouldn't set them up inside, I would just move their trays inside at night and then back outside in the day. If the temp only gets to 32, it won't be that cold right up beside a sliding glass door or near a door or window on your house if you don't want to haul them back and forth.

    Keeping them cool but not freezing will slow down their growth (which is a good thing right now). Bringing them inside and setting them up under lights will speed up their growth (which is a bad thing). You want to aim for small plants with lots of roots by the end of next month. If you get them cranked up too early they'll freak out when they finally get outside in the dirt. Rudbeckias are tough and can probably handle anything except too much moisture right now. Strawflowers LIKE cool weather but would probably not want to be frozen. All them are touchy about being too wet right now. If they are going to be cool, keep them dryer. If you are going to keep them warmer, then keep them damp - because they are actively growing and need the moisture. When they are cool they are usually not growing (except maybe roots) and don't need as much food or water.

  • andreap
    Original Author
    15 years ago

    Thank you all for your advice and comments. I brought in the gomphrenas and strawflowers for the night. The rest I kept outside, but covered the greenhouse with a blanket. All survived, even the tomato seedling that sprouted yesterday. I do have them set up next to the wall of the house, so I guess the 'micro-climate' helped.
    I realize that germinating seeds on the shelves of a minigreenhouse is not technically wintersowing, but seems to work for me most of the time. I usually cover the pots loosely with plastic bags with a few holes in them, then enlarge the holes or remove them when it gets warmer, while lifting or closing the flap according to the weather. It is quicker and easier for me than dealing with individual jugs. (My jugs are all holding water from my rain barrel right now.)
    My brug and tropical hibiscus survived uncovered on the deck and look fine (I forgot all about them in my concern for the seedlings).
    How did your plants do?

  • trianglejohn
    15 years ago

    For as cold as some of this winter's nights have been I'm surprised at what came through. I don't think I lost anything (it is a bit early to tell). Normally I bury certain flower beds in a deep pile of leaves, yesterday I raked those leaves away to expose the sleeping plants. In this one bed where I usually set out potted houseplants and where some of those houseplants creep out of their pots an root into the ground - I found perfectly healthy philodendron vines (not the pothos, the other common one with small waxy leaves), swedish ivy (!), rex begonias, cardamom, and chirita an African violet relative. Some of these guys are on their second year outside.

    For sowing seeds - I go to Sam's Club and buy the large and deep aluminum pans, the ones that caterers and restaurants use for cooking. Very thick walls and about 4 inches deep. I poke holes in the bottoms with a pencil or screwdriver and fill them up with potting soil. This way, when the babies sprout I don't have to water as often (some cell paks required 3 waterings each day) and I don't have to rush to transplant. I wait and let them grow long roots before I stick them in the ground.

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