White spots on berries can be from sun or bugs

I live in Montrose and have a very nice patch of raspberries that produce a lot of berries. The problem is some of the drupelets on some of the berries turn white. It may be only one berry on a cluster of seven or eight or sometimes almost all in a cluster. I have heard it is a virus, or bugs, or whatever. Do you know what causes this?

— Stan

There are a couple possibilities out there. Far and away the most common is simply a sun scald type injury.

In our hot, dry climate, the UV radiation is especially intense and this causes some of those drupelets to turn white. They can be clustered on one side of the berry or scattered individuals throughout it. This condition doesn’t make the fruit inedible, it just looks funny.

Obviously, there’s not much to do about our weather, but good care of the plant (regular watering, fertilizing in the spring) should encourage vigorous growth that helps shade and protect the berries in the summer.

Another option that people sometimes use is to shade the plants by building a structure over the berry patch and putting some shade cloth on top.

The second possible cause for what you’re seeing is damage from stinkbugs.

There are a lot of different species out there, but most of them are 3/8-inch to 5/8-inch long and somewhat rounded or angular in shape. They can be brown or green in color and hard to find as they have pretty good eyesight and tend to hide when we are around.

They suck the juices from the drupelet, which turns white or brown and is usually shriveled up (with UV damage the drupelet is plump and normal looking except for the color).

A thorough spray with Permethrin should clean up those guys if that’s what’s going on.

I have an older Austrian copper rose bush that desperately needs to be cut back. When should I do this, and how far do you recommend I cut back the canes?

— Mary

I think it would be best to wait until March or April to do the pruning.

I’m assuming this is a big old plant you’ll be working on. If that’s the case, you might think twice about cutting the whole plant back to 3 or 4 feet. Because Austrian copper roses flower only on older growth, you’ll be cutting off the flowers for next spring. This doesn’t hurt the plant, you just won’t get any flowers next year. After that, the plant will get back on track and should look great.

A better way to go after this plant would be to try to renovate it. Roses such as your Austrian copper have a suckering type growth habit where you have a bunch of canes coming up at or near the base of the plant.

In renovation, we’re trying to remove big, thick, older canes to encourage younger, more vigorous ones. These younger canes will have more vigor giving you a lusher, fuller plant that will bloom better for you.

I think it would be best for the plant if you did this cutting back over a two or three year period. Select one third to one half of those big heavy stems to remove next spring. Scattering them throughout the plant will help keep the plant looking a bit neater and more normal looking during this renovation process.

These older canes can be a bit thick and the wood of a rose is pretty hard and dense so you’ll have to cut them with a pruning saw instead of pruning shears or loppers.

When you’re removing some of the canes, you could also trim back the remaining ones just a bit to bring the plant into better proportion and make it look a bit better.

I guess my final word of advice (at least for the folks who are thinking about planting one of these guys) is to try to put a big shrub rose like this in a spot where you can allow it to grow to whatever size it wants. It will save a lot of work and sweat and blood.

I don’t envy you the job ahead. Be sure to wear long sleeves and heavy gloves as those Austrian coppers are thorny.


When is the best time to plant a tree in this area? Is it too late?

— Lacie

If the trees are growing in pots, you can plant them just about any time you’d like. There’s very little stress on the plant since you’re not “messing” with the roots very much.

In the Grand Valley, we’ll usually plant up until the first or the middle of December. When the ground freezes up is when we’ll stop. It’s not that it’s a bad time of the year to plant. It’s just too much work to dig a hole when things are frozen.

Dennis Hill is the nursery manager at Bookcliff Gardens, bookcliffgardens.com. Send questions to Bookcliff Gardens, 755 26 Road, Grand Junction 81506; or email .(JavaScript must be enabled to view this email address).


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