Lawns Need Fertilizer Before It Gets Cold

Q. What does a lawn need In November or December?

A. You didn’t tell me what kind of lawn you have so I will assume it is tall fescue or an overseeded Bermudagrass. I like to recommend your final application of fertilizer for the year right around Thanksgiving. This last application of a high nitrogen fertilizer helps keep it dark green through the winter.

            This application must go on before it gets really cold. If you wait too long and apply it later in December you run the risk that your lawn will enter into dormancy and start turning brown. Once it turns brown, it is difficult to get it green again until temperatures begin to warm.

            Hopefully you have been applying a decent lawn fertilizer through the year. Good turfgrass fertilizers have half of their nitrogen content in the organic form or slow release. They also are relatively low in phosphorus compared to the other numbers. If you have been using good turfgrass fertilizers through the year, all you need to apply is straight nitrogen now such as ammonium sulfate or blood meal for organic growers.

            The usual rates recommended on the bag, in my opinion, are much too high. You can usually reduce that rate by 25% easily. If you are returning your lawn clippings to the lawn with a mulching mower you can reduce it to half of the recommended rate.

            You missed the ideal time to remove thatch with a dethatcher. That should’ve been done in mid-September to the first part of October. You can aerate your lawn or punch holes in it with an aerator any time of the year but mid-to-late spring is a great time for that.

Wait for Cold to Pass Before Pruning Grapes

Q. Should I cut my grapes back now or wait until spring?

A. I don’t like to finish pruning my grapes until about March 1. This is because I don’t know what kind of damage they will sustain this winter because of the cold and wind. If I prune them back to very short spurs or canes now, I run the risk of losing my crop or a majority of it.

            I usually prune grapes in two steps in our Las Vegas climate; the first step I remove most of this last year’s growth down to about 18 to 24 inches long. Then I wait for the majority of the winter to pass.

Leaving growth really long through the winter

            The second step occurs close to the first week of March. This is the time when I prune the remainder of last year’s growth down to about one or 2 inches long if I I am producing on spurs and about 12 to 15 inches long if I am producing on canes.

Spur cut back leaving only 1 to 2 inches

Do not cut your grapes back yet. Wait until the major cold weather has passed.

Assess Plant Cold Damage in the Spring and Fix It

Q. Are there are any plants I need to prune or trim down before the frost comes to the Las Vegas valley this year?  I noticed that oleander suffers greatly from frost, foxglove, asparagus ferns, potato vine and a purple flower trumpet flowered plant are kissed when the frost comes. Should these be covered also?

A. Damage from frost will be variable in different places throughout the Valley. There are places which are naturally cold spots and others in windy locations. These areas will be hit the hardest.

            Then we have the variability of the weather. It was not too long ago that we had unusually

Difference in cold damage between two different types of Oleander

warm winters where it hardly froze at all. Then we had a terribly brutal winter with the coldest temperatures hitting us in February when plants were just waking up from dormancy.

            Then we have variability in the plants themselves. As far as oleanders go, there are winter tender types and there are very cold tolerant types.

            My basic advice is to leave most ornamental plants alone. Wait until the coldest part of the winter has passed, or you begin to see the beginnings of new growth, and then remove what has been damaged. Oleander and asparagus fern can be pruned to within a few inches of the ground and they will recover.

Oleander will recover by summer if it is pruned to within a few inches of the ground. in late winter

            This doesn’t hold true with citrus. Citrus planted in cold locations will have to be protected if you want it to survive or you want fruit.

Green Bell Peppers Turn Colors When Mature

Q. Some of my California Wonder bell peppers are turning half black instead of red. Otherwise, they seem fine. It seems it happens the most when it cools down. Are the safe to eat?

 

Mini red bell peppers

Yum Yum Gold Peppers

A. There is a huge assortment in bell peppers. Years ago they all stayed green and when they ripened, they became partially red. People liked them. The market grew for red bell peppers.

Then breeders bred for the development of a solid, red color. Now we have beautiful red peppers that are held on the plant a little longer to get that red color to develop. The same was true of yellow, orange and even purple peppers.

But nearly all of the bell peppers start off green. Producers harvest them when they are large but immature so they stay green. If producers spend a little bit money for seed, get hybrids that turn a beautiful solid color and leave them on the plant long enough, they will get more money for them. And you get charged more at the store.

 We harvest peppers before they are mature if we want them green. However, if we get a cold snap this may cause them to develop their mature color sooner. In your case, I am guessing you have a pepper that turns dark purple when it is mature.

The clue was it was half black instead of red. Your pepper is just fine to eat and it actually might be a little sweeter because of the cool weather. By the way, that purple color is probably anthocyanin, a rich antioxidant.

How to Correct Brown Spots on Indian Hawthorne Leaves

Q. Two of my Indian hawthorn bushes developed unhealthy looking brown spots on their leaves. It started on the southernmost of the two bushes and then the second was affected. These are in the middle of a row of bushes planted along the sidewalk when the house was built in 1986. None of the bushes get a great deal of direct sunlight, but bushes on both ends of the row, with conditions about the same as for these, are looking all right. Can you tell me what is wrong with these two bushes and how to fix it?

 

Indian Hawthorne with leaf browning

A. From the picture this looks like a soil related issue. The soil around the plant looks like it is fairly rocky and I am guessing unimproved over the years. 

I think you'll see a big response by taking a bag of decent compost and spreading it under the plants one or 2 inches thick and watering and in. The other thing you might try is replacing any rock mulch under the plants with wood chips that will slowly decompose and improve the soil. 

If you put the compost down now and water it in, you should see some improvement in the plant when it continues growing in the spring. The second thing you could try doing is spraying the foliage with liquid good quality fertilizer. 

Miracle Gro or Peters would be a good choice. Use one or 2 teaspoons of liquid detergent in a gallon of fertilizer spray to help it penetrate the leaf surfaces. I would try spraying the foliage during the winter. If it's in a warm spot, you may see a response before next spring. Otherwise you'll have to wait until growth resumes early next year.