Just after flowering is usually considered the best time.

Resin

Prune carefully, they don't like much of it. What are you trying to do?

Generally disease-susceptible cherries may be apt to have bacterial or fungal pathogens enter through pruning cuts. Some cherry trees are virus-infected, possibly these can be transferred to previously clean specimens through non-sterilized shears.

Cutting into mature branches also tends to result in new branches shooting off at awkward angles. From what I have seen here trunks of cherries may be prone to simply rotting out where large branches have been sawed off.

"Very few of the prunus need annual pruning. In fact, the majority seldom need attention once the tree or bush has been formed in the nursery, apart from the removal of dead or diseased pieces. It is difficult to over-stress the importance of sound propagation and good training, for a bad start through the choice of a poor or incompatible stock cannot be corrected by culture and pruning in later years...

"While it is true that most prunus do not need annual pruning, many horticulturists believe that even an occasional pruning when needed is definitely harmful. It is difficult to produce any direct evidence that this is so, but there is a danger of certain diseases entering a wound...especially during the winter when the trees are dormant. The best period for large prunings to be removed is before midsummer...

In order to reduce the need for pruning to a definite size and shape, it is important to select the species or variety most carefully before the planting is made"

--Brown (Kirkham), The Pruning of Trees, Shrubs and Conifers, (2004, Timber Press, Portland)

Thanks for all the advice and info.

I do not know if it makes any difference, but sorry that I neglected to mention the cultivar name.

It is an 'Okame' Cherry, which my friend and I planted in her front yard three late Winters ago. When first planted it was bareroot and about 5 feet tall.

By last fall it seemed to have reach a well established state.

Other than pruning out the crossing branches when we first planted it, we have not done any training pruning on the tree. The tree first appeared as if the growers had done a fairly good job, training the tree.

Now we want to raise the canopy a bit, before the lower branches get too thick for a reasonable sealing over of cut time.
These lower branches are about 1/2 inch thick near the trunk right now. Originally I wanted to cut them off when they were half that thickness, but my friend wanted to wait and see how the tree's shape began developing.

Now she agrees that they need to be removed for a better appearance, and I am hoping that by now, we have not waited to long and caused pruning those branches to put the tree at risk.

According to the advice above, I understand that pruning while the tree is dormant is good. Yet there is also advice that pruning in early summer is better, since sap will flow better and help to avoid invasive fungi, and diseases from entering the wound.

Considering the extra info I have now provided, which of the two above listed but different advices is best?

Katrina, the 'best' time for nearly all tree pruning is dormant season, late dormant season to be exact. But, the difference between the 'best' and 'worst' times is not huge. Don't get too stressed about that factor. If one simply avoids pruning when A) The tree is making leaves, ie. Spring, or B) the tree is shedding its leaves, ie. Fall, everything will be fine. And those 1/2 inch thick branches are by no means too large for the tree to handle having them removed.

The idea that a flowering tree should be pruned right after flowering is that by so doing, you are not removing flower buds for next year. This is true, but it is far outweighed by other advantages of dormant-season pruning. These are: You can see the structure better, you are allowing the tree to have open wounds for the least amount of time before resumption of growth in Spring, the plant will be poised to put its energy into the branches you leave on the tree and will not have wasted energy in producing leaves only to have them cut off, and finally, disease pressure is usually lower at this time of year.

FWIW, the organization I work for manages perhaps thirty to forty thousand individual trees. We prune year round, out of necessity, avoiding only those two times mentioned above. There are a few individual variances we follow as well. We prune no oaks during during growing season, as this can open up the plant to oak wilt. We prune no honey locusts on wet days, as this can set the stage for nectria canker development, and any shearing-type pruning such as Japanese yew hedges are done in summer, no later than August, so the wounds can close before winter, thereby avoiding dessication of the cut stems. But otherwise, you really do have a large window during which the pruning can safely (For the tree) be done.

There may be a difference from one region to another in terms of pathogens and host susceptability, but at least where I do my work, I wouldn't think twice about whether or not to prune a cherry, or any other ornamental tree, during late winter. I don't wish to come across like mine is the last word on the subject, but I can state unequivocably that I've done literally thousands of such prunings with no harm done to the plants. Trying to help here ;^)

+oM

+oM, thanks for the extensive explanation. I tend to highly agree with your above listed opionions.

The issue for me is my novice status of growing ornamental cherry trees, and it is reasuring to read advice from those like you who have more extensive experience than mine, concerning such tree prunings.

The roots from our cherry tree are breaking through the top of the lawn surface in several places; what can I do about this?

kiknd regards.

Robert

My decorative cherry has large branches hanging over the house roof too close to the house. We need to remove some large branches. Is that best done after flowering but before mid summer?