Q: How do you get seedless grapes? I bought a grafted vine that with a label that said it would have seedless grapes, but the grapes have seeds. Can something be done to make them seedless?

A: That is a good question. How can you get seedless grapes, or seedless watermelons, for that matter, if there are no seeds to grow?

In the case of the grapes, you hinted at the answer. Grafting is the process of taking a piece of a plant with a desirable characteristic and getting it to grow on another plant that doesn't have that characteristic. If a plant with a desirable characteristic can be propagated by seeds, it is easy to get more of that plant. Or, if the good plant can be propagated by taking a cutting off the plant and having roots grow on the cutting, it is also easy to get more new good plants.

Unfortunately, it is often the case that the cutting will grow very few roots, or no roots at all. In that case, we can often propagate it via grafting. The bottom section of the graft (the rootstock) can be a seed-grown plant or a cutting with its own roots. After it has grown to the proper size, the top can be cut off, and the good plant (the scion) can be grafted onto it.

It is possible that the rootstock of the plant may send out new branches of its own. These must be cut off as soon as they are noticed. In the case of your grapes, it seems the rootstock has taken over and is a variety that produces fruit with seeds. Or, it may be that the plant you bought had the wrong identification tag and was never actually a seedless variety.

You have three options. Leave the plant as it is and enjoy the seeded grapes. Dig out the plant and replace it with the variety you wanted. And, lastly, cut off the top and graft on a new scion of your own. Grafting should be done in the spring, so you will have plenty of time to think about that option.

Occasionally, vineyards will replace an entire crop of grapes by grafting on a new variety in the entire field. This is rare, but it is faster and easier than replacing all the plants with small young ones that will take longer to get the field back into production.

OK, so what about seedless watermelons? They don't live long enough to get a woody stem that can be grafted. So how do you get seedless varieties of annual plants?

There are actually a lot of seedless flowers and shrubs grown in our gardens. Any flower whose sexual parts have been replaced by flower petals to create a double flowering plant with lots of flower petals will be seedless.

These watermelons, and some other annuals, are hybrids. In other words, they are the specific offspring of parents that produce seedless or double flowering babies. In the case of watermelons, one parent has a normal number of chromosomes, and the other parent has twice as many. The resulting offspring is a plant that will produce a watermelon trying to grow seeds with three sets of chromosomes, and the seeds won't mature within the melon.

As you eat a seedless watermelon this summer, remember there are fields growing both of the watermelon varieties needed to produce the third variety that will grow the seeds that will grow watermelons without seeds. In fact, there may even be fields of the grandparent varieties needed. That is a lot of watermelons!

Double flowering plants can't occur in nature for very long. They don't produce seeds, so once the, say, rose bush, camellia, petunia, cherry, plum, almond or other double flowering plant dies, there aren't anymore. But once grafting and other propagation methods came along, these pretty plants were kept alive. Not only do they have the benefit of being pretty but they are also low-maintenance because they don't produce messy fruit. Of course, if you want to eat almonds or cherries, don't get a double flowering variety.

Email questions to Jeff Rugg at [email protected]. To find out more about Jeff Rugg and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.