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trillium_z5mo

How late can you plant perennials, shrubs, etc?

trillium_z5MO
19 years ago

Hi,

I have read a few threads on this subject and I'm still uncertain of how late I can plant. Quite a few people said fall is a good time to plant because it gives the plant time to develop strong roots before the heat comes on.

When you get a chance please answer these questions:

1. How late can I plant perennials?

2. If the cut-off date is fall, exactly what month is the lastest I can plant?

3. Can I plant Juniper trees in fall? (up to what month)

4. As I understand some decidious trees should not be planted in fall b/c they are marginally hardy in zone 5, such as an evergreen Magnolia (Brakens Beauty). Can a sweetbay Magnolia be planted in fall?

5. Up to what month can ornamental grasses and shrub roses (i.e knockout) be planted?

5a.Why is a plant at risk if planted in fall? or right near the time ground freezes? Does the ground freeze all the way down to where the roots are and then kill the plant?

6. Last question what does bareroot mean, how is that different than b&b.

Thank you so much for your anticipated response to these many questions.

Comments (9)

  • Lenny2
    19 years ago

    It is my understanding that it is preferred to plant trees/scrubs/perennials in the fall. You must still water them and fertilize just like planting in spring. I plant until ground freezes (at all)
    You can get good info from your local County extention office on this topic.

  • cantstopgardening
    19 years ago

    I've read that you can actually plant throught the winter. It just wouldn't be very easy because of frozen soil. And everything needs to be watered well. Not a job I'd want to tackle when it's below freezing.

  • apcohrs
    19 years ago

    You can plant shrubs and trees until the ground freezes solid.

    However, up north, planting perennials in the fall is much iffier - not due to the cold, but due to frost heave during the winter.

    My mortality rate is about 5 TIMES greater for fall planted perennials than in the spring.

  • SandL
    19 years ago

    All of my gardening books say to stop planting when the ground freezes.
    Presently, I'm still preparing two shade beds and buying all the 60% off hostas I can get my hands on before winter is upon me. For those beds that are already done (which is hardly any) I'm starting to winterize.
    If you are a glutton for punishment and want to freeze your patootie off while digging in rock hard, frozen ground - go for it. However, I don't think your plants will benefit since their roots will have a hard time establishing themselves in the soil.

  • mrmorton
    19 years ago

    Well, I work for a landscape company, and have to deal with this concern every fall.

    Typically, we do plant shade trees, ornamental trees, and deciduous shrubs right up until the ground freezes. Certainly it is better to give them time to establish a root system, but we have had pretty good luck with this practice.
    I would NOT plant evergreens this late in the season. The last date for evergreens is Oct. 15th. They simply do not take well to late fall planting.

    Perennials should be in the ground by now. Another poster was right in that without an established root system, frost heaving will occur. This raises the plant out of the ground and will often kill the plant if not rectified.

    They key thing I stress to folks is to make sure plants get adequate water. So many people think because the temps are cooler that they don't have to water. This is a big reason why a lot of plants don't survive the winter. Please water!

  • plantman314
    19 years ago

    I plant everything I can until the ground freezes. The only time I've had problems with late planting of evergreens is when they exposed to too much and get winterburn.

    From school I know some deciduous ornamentals do not always take well for fall planting. This is mainly due to shallow root systems, but a 4-6" layer of mulch over the root ball will usually provide sufficient protection.

    Fall planting is preferred because even in winter dormancy the root system of a plant will still actively (,but slowly) grow. Therefore they have a headstart when summer heat and drought begins.

  • quip
    19 years ago

    Former neighbors had great luck planting living Xmas trees every year. They did not leave the trees indoors very long (perhaps 2 days). Holes were dug early (like now) filled with straw, and covered with plywood. Topsoil removed from hole stored in garage to avoid freezing. Trees planted after holiday have matured into beauties with fond memories.

    So evidently some people can plant (even evergreens!) really late and succeed.

  • Joan Vella Smith
    6 years ago

    Perrenials in Aug