Also Known As Rose Replant Disease!
Rose soil sickness often occurs when we plant a new rose bush in a space previously occupied by another rose bush.
We tend to re-assess our rose beds, and decide to remove one or two, while replacing them with some new and wonderful bushes that we noticed in the new rose catalog we have been studying over the Christmas holidays.
Removing the old bush and giving it to a friend, we plant our brand new purchase in the same hole, dug to remove the departing bush. Growth is slow, bloom production is limited, it just doesn’t seem to “take off” and grow.
It “sulks” and just “sits there”. The cause of this strange behavior is often referred to as “soil sickness” or probably more correctly, “rose replant disease”.
The problem is that it can’t really be a disease because up till now, nothing has been identified as a cause of this apparent “disease”.
In fact, Rosarians are divided over whether it exists at all, even though it has been observed in action in roses and fruit trees. (…apples, pears, quince, plums and cherries to be exact, although it does seem to be more about the rootstock the tree is grafted onto, rather than the tree itself… anyway., enough of that!)
The strange thing is that if you plant any other type of plant (i.e. not another rose bush) in the hole vacated by the old rose bush, it doesn’t occur, so the idea that the departing bush has given off some form of inhibiting chemical into the soil cannot be true. [This, I am told is called “allelopathy“.]
Another theory has the roots giving off toxic gases to fend off disease. Others have suggested mineral deficiency, fungal build up, eel worm nematodes, Armillaria soil fungus…and probably smoking, caffeine and high cholesterol!
The fact is, there is, as yet, no definitive cause and that means [bit of logic coming up now] there can be no cure!
So What Can We Do About It?
Well, first of all there can only be general guidelines, but something must be done, as rose soil sickness is reported to exist in the soil for up to 20 years. That’s twenty years after you dug out the old rose bush!
Commercial rose growers leave the soil to remain fallow for several years.
You could plant the new rose in a new location and leave the old location to sit for a few years before replanting.
Most of us do not have the luxury of space so we have to do one of two things: remove a good portion of the soil and replace it with new or plant the new rose inside a cardboard box for protection.
The soil removed could go anywhere else in the garden as it isn’t toxic and the cardboard box would deteriorate over time….as long as it wasn’t wax coated!
Personally I dig out the old soil and replace it with new, fortified with good rotted compost or manure, and a handful of slow release, high nitrogen fertilizer.
I do this with all new bushes, just in case the mysterious rose soil sickness creeps up and puts my new babies to sleep!
There is no agreement on the causes of rose soil sickness and thus no cure. Until there is, the best thing we can do is change the soil, improve the soil and keep a watchful eye…three things most rose growers do anyway!
Be vigilant and prepared whenever you re-plant or replace a rose bush.