Juniperus virginiana and Juniperus communis – we have a boatload of these plants and they are nice! I remember growing Juniperus virginiana and Juniperus communis years ago and they didn’t look as good as they do today. The bottom needles would turn brown and the plants wouldn’t let go of them. Persistent brown needles are not a characteristic that you want in your Junipers. They did make great kindling for our burn pile though, igniting as fast as a newspaper.
Fortunately, we’ve learned and we haven’t had a Juniper fire since. Go figure.
Johnson’s Nursery now expertly grows these native junipers in containers way better than I ever could. I’m pretty sure it has to do with the water. They’re now grown extremely dry. When I was in charge of the growing, I was watering them daily. Not good. I suspect J. communis and J. virginiana are extremely susceptible to root rot diseases. During extended periods of excess moisture, the disease takes hold and kills off many of the roots. In containers, these root losses cause plants to lose portions of the plants very quickly, thus the needle browning from the bottom up on J. virginiana. In our fields, we seldom see the problem with the browning from the bottoms up, but we do have inconsistent success with transplanting. It is not uncommon to lose 30% to 50% or more of seedling J. virginiana plants produced when transplanting B&B. I suspect the plants in the field lose portions of their root systems during wet periods, but not as severe as those in containers. The loss of roots becomes evident only when the plants are transplanted B&B and don’t have enough roots in the ball to recover. We don’t see these kinds of losses when we transplant the named cultivars. These all have been grafted onto Juniperus chinensis ‘Hetzi’ rootstock, which is far less susceptible to root rots.
If you have ever tried to purchase native Junipers, you may discover that they are difficult to find. It’s not hard to obtain cultivars of the various kinds, but the straight species are rarely available. The root rot problems have made them uneconomical for most growers to produce. Now that we are successful with production in containers, we often have a steady supply of these outstanding native plants. We are continuing our work to develop a B&B production technique that will allow us to have transplantable, large-sized J. virginiana in the future. Fortunately, once they are planted in the landscape, these native junipers are not very fussy and perform admirably.