Hello, I am just wondering if there's anyone out there who has had success growing a Japanese Maple in the colder growing zones. I live in southern Minnesota and while the winters are usually not too bad here, we do get one or two cold snaps in the -20's, so I have always hesitated on trying these. It seems like they are all rated for zone 5/6 or higher. :( However, they are so gorgeous, I just have to ask - I'd love to have one! Any recommendations would be appreciated. thanks!
Here they are for those that don't have access to Plant Files
Gwen's Rose Delight
Viridis (Acer palmatum var. dissectum)
V Corbin (Acer palmatum var. dissectum)
Ogurayama (Acer shirasawanum)
Junihitoe (Acer shirasawanum)
I would definitely doublecheck those hardiness ratings with other sources before you buy anything--Plant Files does have mistakes sometimes and since JM's are often pricey I'd want to find a couple other sites that list those as zone 4 also before you believe it (Zone 4 is going to be pretty borderline for JM's, even zone 5 can be tough for some of them). You might check out Davidsans JM's, he is in zone 5 and specializes in JM's that are good for colder climates. http://www.davidsansjapanesemaples.com/
I am zone 4/5 border, with -20 possible any year. I love JM's but I stick to container growing. I winter the plants in an unheated garage and only grow the hardier varieties. So far, it has worked. Though growing in the ground might work some years, or even most years, it only takes one bad year to kill your beautiful trees. I don't think it is worth the risk. It isn't just the winter cold, they can also be done in by late spring freeze.
gsox thx for looking up the jm zones - in z4 i would be very careful - of the list i am familiar with sango kaku and based on reports i would not plant in z4 - same with beni kawa - i have a gwen's rose also called shirazz and it does well here although i have to agree with granite stick to containers.
The late, great JM expert, J.D. Vertrees, wrote that the aerial parts (trunk and branches) of Japanese maples can withstand winter freezing and air temperatures down to 0ºF (ONCE ESTABLISHED). However, the roots can survive to only 14º F. This is rather confusing until you realize that when planted normally in the soil, the plants can withstand extreme temperatures because the roots are protected sufficiently in the deeper soil, especially if properly mulched. The roots of newly planted trees, however, are not necessarily protected sufficiently, hence the importance of correct mulching (ideally 2" of coarse bark).
Unless you have a microclimate somewhere in your landscaping, I think you must stay with container-grown Japanese maples, which can be quite beautiful and versatile in the garden.
zone 4 is definitely container country for any A.p, Aj, and A.s . , and any hybrids in such group. You "may" be able to grow Griseum ( Paper Bark Maple) there . If sugar maples grow there Giseum should...they seem similar in habit but are safer in zone 5 even extreme areas of zone 5. I do know that Psuedosieboldanum SSP Psuedosieboldianum is allegedly zone 4 and should grow there... I know it is grown in Mn . It is an Asian maple and is JM like in most every respect and should at least give you that look. With containers you can grow any JM virtually anywhere.There are pluses and minuses to container growing as there is with everything in life basically much more work but many more placement opportunities . Container growing it is the safest method to grow any Jm in northern areas. But as said you may want try a Pseudo and possibly a Griseum getting a tree that is several years old, not a twig and placing it in a sheltered area and mulching well Davidsan
One thing you may want to try is the new laceleaf elderberry. Many say it looks like a laceleaf JM, but it grows in zone 4, is a dark red/purple, has spring flowers, and fall berries. The patented version is also lemon scented. Doesn't get as big as a JM, and may die down each year, but in summer/fall, you have something very similar, without the fuss.
I lost a Viridis to -17 last winter. It was an established tree, well mulched, in a sheltered location. I'd go here to source or purchase the hardiest cultivars and to get the best planting advice, whether in the ground or in a container.
The lacy black elderberries are pretty and hardy shrubs, but don't substitute for a JM! I've heard the so called Korean maple looks similar to a JM, and are hardy, but I have yet to see one so it is hard to know whether they are good substitutes. Anyone out there have one?