Garden Talk: Should weeds in new lawns be removed?

Jill and Rick Van Duyvendyk answer all your gardening questions in Garden Talk on 650 CKOM every Sunday morning from 9 a.m. to 11 a.m.

Here are a selection of questions and answers from our Aug. 4 show.

Q: What is the best weed control to use for new grass?

A: Just leave it alone, as the weeds act as a great cover crop to protect from the heat. Mow them down so the weeds don’t go into seed but wait until the grass is around two inches tall before cutting it. Then just keep cutting it. Most of those weeds are annuals, and next spring your grass will be filled out and your weeds will disappear.

See Dutch Growers lawn guide here.

 Q: What are those mossy, cotton candy looking things on my apple trees?

A: They are summer tent caterpillars making a nest. Spray them with a product called BTK. It only affects the caterpillars and will not hurt the apples.

Q: What is the best variety of grape to grow in the Regina area?

A: Valiant and beta. Plant some of each because they need to cross-pollinate. They can be found at almost any garden centre.

Q: Is it too late to trim spruce and maple trees?

A: No, now is the perfect time to prune them. Any time after July 1 is good to prune, especially maples and birches. After the end of October, you can’t prune them again until next summer.

Q: What about pruning other plants right now?

A: All trees can be pruned, it’s not going to hurt them. Don’t prune early blooming shrubs because they set their buds in the fall on the old growth. In August they’re not going to put on that much more growth. Forsythia, lilacs, double-flowering plum, flowering almond, all those early, early bloomers should not be pruned right now.

Q: What about elm trees?

A: You can’t prune elm trees in Saskatchewan until Sept. 1. When you cut a branch it emits some sap which attracts the elm beetle, which could be infected with Dutch elm disease. It is illegal to prune them between April 1 and Sept. 1.

Q: Is now also the time to be planting trees?

A: Now is a great time to plant trees as long as they are kept watered. If garden centers have stock, you can plant all summer long. It’s an old wives’ tale to only plant in the spring. Make sure they are watered properly, with the hose right up against the trunk to water the root ball that came out of the pot. That root ball can dry out, so water a little bit daily, as if you’re watering the pot.

Q: What can be done about grass in an acerage in Estevan being taken over by cactus?

A: About the only way is to dig them up, because cactus will spread seed when they flower. In years when you have a little early moisture like this spring they flower profusely. Make sure to dig them before they spread the seed.

Q: What do I need to do to care for an avocado plant that is growing in a four-inch pot and now has an eight-inch stem?

A: Don’t put it in a large pot until you can see the roots hitting the edge of its container and wrapping around. If it has no leaves wait until it has two sets of leaves, then pinch out the top. This will allow it for branching and bushing. Be patient, give it lots of light, and keep it moist. Keep it in a smaller pot with about an inch of space on either side of the seed.

Tip: Put the seed in a plastic bag with a paper towel first and soak it until it seed cracks open then put it on toothpicks in a jar to produce roots faster.

Q: What can be done about a large, mature spruce tree showing signs of scale?

A: When the scale get into the crawling stage (when they are soft and a little fuzzy) then you can spray with just about anything. You can hit them with End-All, Bug X Out, pretty much anything. They are in the crawling stage at this time of the year.

Q: When is the best transplant time to transplant rhubarb?

A: Spring. About the middle of April.

Q: Can haskaps get fireblight?

A: No, haskaps are in the honeysuckle family. Contoneaster, mountain ash, apples and flowering crabs that will get fireblight.

Q: What are the little black bugs on kale plants in Swift Current?

A: They could be flea beetles or black aphids. Both of those you can hose off with cold water.

Q: What are the black dots on my Northern Garden Purple Spire ornamental crab trees?

A: It could be caterillar excrement. If you can rub it off, it’s probably that.

Q: How do you keep blackbirds out of the garden?

A: Try a scarecrow sprinkler that turns on when it detects motion, it will scare the birds away and not overwater the yard. Or put a garden net over vegetables.

These questions and answers have been edited and condensed.

Read more

• Expert urges extra watering for plants, trees
• VIDEO: Blooming tulip patch draws thousands of Saskatoon visitors