Rose flowers do not open well
by Marilyn
(Mountain View, CA, USA)
Flowers do not open well; they turn brown at the edges and fail to open as they should. It was a gift and I do not know its name but the flowers are pink and white.
Doug says it sounds like either powdery mildew or botrytis. There are articles on controlling either/both here.
Small blooms on roses
by Virginia G
(Little River, KS)
The small blooms on my rose bushes are few and small when I do get any buds. I used to have very large flowers and do not know what has happened. I fertilize regularly, and spray for black spot be-weekly. Not only my new plants, but also my bushes that in the past were healthy, all look spindly and do not want to bloom. What can I do? Or what could I have done that has caused this problem?
Doug says that spindly plants are the result of stress. You can "normally" look at feeding too little, watering too little or too much or not enough sunlight.
If you're using a good supply of compost in the early spring and late fall - you should be fine. A top up of fish emulsion after each bloom flush usually works to keep the strength up.
If the sunlight levels haven't decreased because of surrounding trees and bushes growing up - and if the the rose is getting a solid 6-8 hours of full sun a day - then you're fine. Any less and you should move it.
Watering - usually 2 inches a week should do it unless you're on a heavy clay soil - and then you'll have to adjust depending on the water content in your soil.
The other option - is that the top of the rose has died. And the new spindly growth is coming from below the rose graft. This means you're growing the root stock and not the desirable rose. You don't say what kind of rose you have so I don't know if it's a grafted rose or not (almost all roses except for shrub roses are grafted).
So a reduced or non-existent bloom often comes from a rose where the majority of new canes are the root stock but there are some of the desirable canes left alive. The new root stock canes don't bloom but the old desirable rose ones do.
That sums up the reasons for small blooms on roses - and I hope that gives you some sense of what to look for.
no rose blossoms
by debbie
(Southern Gulf Islands BC Canada)
My rose has lots of beautiful green leaves, but no buds or blossoms. Should I cut it back, and if so, how much? Last year the deer got in and munched away and I had wonderful blooms. I don't want to use deer as my pruners.
Doug says that if you have no blooms and it's mid summer - then it's quite likely that your rose top (the grafted upper part) is dead and the rose bottom (rootstock) has taken over. Rootstocks are great for producing energy to grow great flowers but typically have poor or no flowers themselves.
So you likely don't have a living grafted top.
Having said that - you don't say what kind of rose it is. So if it's a rose that blooms on old wood (last year's growth) and the deer ate all that, then this year's growth will bloom next year. And if you prune that off, you won't get flowers again. Those kinds of roses need to be protected from deer. :-) (Fencing works)
So that's the deal - it depends on the kind of rose you have what's going on with the bloom.
But in any case, I wouldn't prune it back hard at this time of year anyway if it's a shrub rose. If it's a hybrid tea and not blooming - you've probably lost the tops and cutting it back is pretty much useless (digging it out will be the appropriate response) :-(
