HG: Homegrown Column December 13, 2008
I have a question about grapes. Not all of my grapes ripened before the frost, so I did not pick them. Now, I have large clusters of grapes on the vines and I want to know if they need to be removed? Will leaving them on (in hopes of the birds feeding on them) interfere with next year’s production? The grapes are very sour, and so far, I have not noticed birds feeding on them.
Enjoy your column very much.
There shouldn’t be anything wrong with leaving the grapes on the vine. I would expect the birds will take care of them in time. Any that they leave will dry up and turn to raisins which will fall off by the time the new growth pushes out next spring.
If the grapes were to interfere with next year’s production (and I doubt that), that has already occurred, and it’s too late to do anything about it.
The situation I’m talking about is called alternate bearing. I don’t think this is much of a problem with grapes, but fruit trees (usually apples) sometimes get into this problem where they overproduce one year and then have nothing or next to nothing the next year.
If the tree doesn’t bear much fruit because of frost or some other reason, the energy the plant had on hand for fruit production goes into increased growth and storage. The following year, that abundant growth will bear fruit, abundantly.
You’ll get zillions of fruit set on the tree, often more than the tree can support so the fruit can be small and of poor quality. The problem is then perpetuated because the tree spends all of its energy trying to ripen that bumper crop and doesn’t have anything to save for the following year resulting in a light or nonexistent crop.
It becomes a vicious cycle.
The solution is to physically thin the crop to restrict the plant to bearing only the fruit it can sustainably ripen.
This is done usually in late spring or early summer (though with grapes it can be done when the grape berries start to change from bright green to their mature color in summer). There’s usually a natural thinning period this time of the year when the tree will drop the small, developing fruit but sometimes it needs a bit more encouragement. How much depends on the particular type of fruit we’re dealing with.
I don’t know why the grapes were so sour. Perhaps the vines are young? Perhaps the particular variety (wine varieties aren’t very sweet)?
One last bit of information: If this happens again next year, after the frost, grapes are still fine to eat though they won’t last long. The frost tends to increase sugars in the berries so they may be a bit more palatable.
What time is the best for planting apple, peach and pear trees?
When to plant depends on the state the plant is in.
If it’s growing in a pot, you can plant them any time. That’s why we like growing things in pots. When you plant them, you’re not disturbing the roots much. You’re just slipping the plant out of the pot and into your garden. It’s just changing addresses, and it doesn’t matter whether it is 32 degrees or 102 degrees outside
We plant container plants nine or 10 months a year, 12 months if the weather cooperates, stopping when the ground freezes up in the winter. So you still have a little time if you want.
However, if the plants are bareroot or packaged (that’s just a bare root plant that has some packing material around the roots to keep them moist), then you really should plant them early in the spring, from late February to early April.
It’s important to plant bare root early in this area since we warm up so quickly in the spring.
You want the plant to have as much time as possible to root out and replace as much of the root system that was lost in digging and storage before hot dry weather sets in.
A balled and burlap (B&B) plant is usually a larger plant that’s been dug with a soil ball around the roots, which is wrapped in burlap and usually a wire cage to support and hold it together.
B&B can be planted about the same as containers, though I’ll sometimes take a short break from planting them during the hottest part of summer.
That really depends on how the B&B is held in the nursery. Most of the time they’re lined out and sawdust or wood ships are piled around the rootballs to keep them moist.
As time goes on, the tree initiates roots into this material and those roots are damaged or lost in moving and the tree can sometimes go into shock. The tree almost always recovers, but it’s alarming for the homeowner. Also, there are methods for holding B&B to minimize or eliminate this problem.