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julia_c

Starting Perennials/Biennials from seed

julia_c
11 years ago

Hi everyone, I'm very new to growing from seed. So far lots of success with the annuals, but I would also like to try starting some perennials from seed. From what I've read so far, summer is a good time to begin the seeds. So my question is what happens to the seedlings over the wintertime? Should they be transplanted to the garden before first frost or should I pot up and continue to grow them under lights indoors through the winter and transplant in spring? I'm in zone 6 and while this past winter was extraordinarily mild, we can also have harsh winters. Not sure if this info helps, but I'm particularly interested in starting some siberian irises and some digitalis.

Julia

Comments (4)

  • morz8 - Washington Coast
    11 years ago

    Julia, siberian iris (and most iris) will usually germinate best if given a period of moist warm condition, followed by several weeks moist cold, then will germinate when temps are a little warmer but still cool. Several weeks each of approx 65F sown moist, then 40ish or overnight freezing, which is followed by germinating while temps are right around 50F. I like to sow and place the pots outside in Fall, let mother nature take care of the cycles. You can duplicate what would happen to them if self sown by the plant when ripe by sowing and keeping the pot warm a few weeks, moving it to your refrigerator for a few weeks, then end with a cool room, still taking care to keep them damp/moist. It's that last cycle I can have a problem with, I don't have a good place to provide that 50ish range - unless I put the pots outside.

    The digitalis should germinate, surface sown, in about 14-21 days. That should give you time to plant out in Fall with them having time to establish before harsh weather.

    Depending on what you are sowing, summer isn't necessarily the best sowing season. Temps too warm can delay germination just as temps too cool may - it all depends on what you are sowing and you have to consider each individual seed then try to meet its needs.

    Try the Clothiers database for suggestions on what conditions seeds may need to germinate...most of the information there is quite reliable, its one of the better online germination databases.

    Here is a link that might be useful: Clothiers

  • susan2010
    11 years ago

    I have limited indoor growing space, so I usually end up starting my perennials after I've moved my tomatoes, peppers, and herb starts out to harden off. That was a little over 3 weeks ago. They have now all mostly germinated. I'll probably plant them out some time in early to mid July. Our autumns are getting longer and milder, and that seems to give them plenty of time to establish before winter.

    I'm starting a bunch of things this year, including delphiniums, coral bells, several different bellflowers, columbines, coneflowers, shasta daisies and some other things I'm forgetting.

  • lam702
    11 years ago

    I wintersow most of my perennials. I always do my foxgloves and delphiniums this way, delphs and a few others need some cold treatment to germinate well. Because most perennials don't bloom the first year, I usually wintersow them, then move them into larger pots for the summer, then,in early fall I move them into their permanent beds. This way, I can have flowering annuals in their beds for the summer, instead of the perennials which won't give me any flowers until next year. I have a batch of wintersown delphs, foxgloves, columbines and armeria in pots now, which I will plant in Sept. For me, in zone 5, summer is a bit late to start them, as they are not always big enough by fall to be hardy enough for winter.

  • julia_c
    Original Author
    11 years ago

    OK so I need to rethink my plan here. It doesn't sound like summertime starts will work for me. Looks like I will be trying out wintersowing this year. hpny2, I like your idea of keeping them in the pots throughout the summer and then planting out in the fall. What size pots do you find yourself using for the foxgloves and delphiniums? And are you giving each plant its own pot or is it more of a community pot setup?

    morz8 that Clothiers database is excellent!

    Thank you to everyone for sharing your knowledge. I still have a lot to learn, but I'm very appreciative of the guidance you offer.