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November 17, 2012

Is it too late to put down pre emergent in my rock during November?

-- No, it's probably fine right now unless you see a lot of little weeds coming up. Do it before any rain comes and washes it away.

How thick should the plastic be in a greenhouse?

-- The thickness of the plastic really doesn't make any difference as far as its effectiveness in a garden condition. What you can do is get higher grades of plastic because some will last longer than others, but typically our winter season is short. 6 mm should be just fine.

How often should I water my citrus trees?

-- In the heat of the summer, once every 5 to 7 days. In the Winter, once every 10 to 15 days.

I’m going to remove some Agaves because of some snout weevils, can I replace the Agave and put it in the same hole?

-- If you have a problem with weevils in your neighborhood, chances are they're going to be hard to eliminate. I would probably go into something different like a Desert Spoon or a Yucca. There are a lot of plants that are similar in form, but aren't Agave and don't get attacked in the same manner. You don't have to treat for them because the weevils aren't going to attack those the way the do with the Agaves. When you replace the Agave, clean out any grubs that you see and you should be fine.

I got 5 pecan trees, but in 2 of the trees the nuts are splitting out and they're starting to grow already.

-- Typically when you have fruit that acts atypical or has character problems, it's most likely due to the weather. It wouldn't be from watering too much because they like a lot of water. It's pretty hard to overwater a Pecan tree.

I have an apple tree and it seems that whenever new leaves come out they are burning on the edges. They are getting irrigation and get drip water several hours once a week.

-- This time of year if you're watering once between irrigations you should be fine. You might want to put some soil, sulfur, or gypsum around the trees to sweeten up the soil. It's going to make it a little more acidic and make it drain a little better. Make sure to fertilize it in early January with fertilizer that contains Zinc, Manganese, or Magnesium because there is probably a little bit of a deficiency in there.

I have a 5 gallon peach tree and I want to transplant it, when would be a good time to do that?

-- As soon as the leaves go off of it, pretty much anytime between November and January. Wait until it gets a little colder.

I have a lemon tree that's 40 years old and 5 years ago it had a wonderful, huge crop of lemons. The whole tree split in half, down the main trunk to about 4 feet above the ground. Since then some new growth came out of the main trunk. It's been 5 years since then and it's grown pretty tall, but it's never grown any fruit since then.

-- The root stalk has most likely grown out of the ground. To fix it, go out there and everything that starts from the bottom, 6 or 8 inches, you want to cut off, except try to find the main, original trunk. If it does produce without doing this the fruit won't be of very good quality. Prune all of it back and let it grow back and it should grow back really fast. Prune everything back to the main trunk, discard all the other foliage, and you'll make a tree again within a year or so.

I always mean to put down a pre emergent weed killer, but I never get around to it and then weeds come up. When would be a good time to put it down?

-- If you don't have anything germinated yet, now would be a good time to put it down (November). As the weather changes, that's when you're going to get all the winter weeds germinated. As you spray it down make sure to water it in, that's the key.

We have a Pomegranate bush and it's about 18ft tall and we want to trim it back when it goes dormant, is that the right time to do it?

-- That is the perfect time to do it. And if you want to get the best quality fruit, you can prune it back to about 10 or 12 feet. Do it anytime from now to the middle of January or February before it starts to leaf out.

What's the best color of the exterior of the pot so it doesn't get too hot from sunlight?

-- White will reflect heat more than the dark colors will, but when the plants get bigger and shade their own containers it doesn't make much difference. What would make more of a difference, would be the type of pot. If you want the type of pot that adds the most insulation you would look for something that is made from a lighter product like clay, versus plastic.

What are the best vegetables to grow in pots?

-- Peppers and tomatoes are very popular, but this time of year (November) are all the leafy greens (broccoli, cabbage, kale, cauliflower, etc.) and all the root vegetables.

I'm thinking about putting in a hedge and I was thinking about putting in 3 or 4 sour orange plants, will they be a good barrier?

-- They will be an excellent barrier, but they will take a little more water than some of the desert plants would. It also depends on the style of landscaping you have, but as an overall hedge it's really hard to beat sour orange. Some other options if you have a more desert landscape are Sages or maybe even a Green Hop seed.

I've got a Chilean Mesquite and it's turning yellow.

-- It kind of should turn yellow this time of year (November) with the change in weather. I wouldn't be very concerned with it at all. If it's a big one, once a month is more than adequate. It's going to get yellow and it's going to drop its leaves in January, that's pretty normal for it.

There's a pest that's invading Bougainvilleas. What should I do about that?

-- You don't really have to do anything. It's got to do with the weather we're having and they are going to naturally cycle out. It seems like they're already on the downhill slide so I wouldn't take the time to spray them. Bougainvilleas grow back very fast and will come back and repair themselves quickly in the Spring when it's hot. If it appears to be a problem in the Spring or early next Fall then I would use a spray as a great way to get rid of the bugs.

We have a big Mabel orange tree, but all the new growth is curled and mottled, it also has a shine to it?

-- It's probably being attacked by thrips. Thrips are a native insect here that are all over cotton and citrus and lots of different things and they get into the new growth and they scar the tissue. Normally on a big tree, I wouldn't be too concerned, I would let nature run its course and the good guys will come out when the next flush comes out, when there's plenty of fruit around, and they'll eat those little thrips.

I have a tree rose that happens to be called Popcorn and several clumps of the leaves are pure white in the middle of the other greenery. I had given it Iron, but it's a little passive.

-- It might be a little bit of a virus, but it should cycle out before it gets worse. If you cut it back this Fall, I would fertilize it right now (November). Now is a great time to fertilize Rose if you already cut it back and set them up. Use something that is balanced, like a Miracle Grow is fine, just make sure it has all the miners in it. Fertilize it right now and it should grow and you should have some wonderful roses in the Spring.

I have some spurge, how do I get rid of it?

-- The spurge will go away in the wintertime when it gets cold anyway. What you really want to do is put down a pre emergent for that spurge in the Spring, like at the end of February. If you put down a pre-emergent it will prevent the spurge from coming back. You might want to put a second application down around the first of June.

I have a Mabel orange tree and it seems to be dormant, not growing at all.

-- Well Mabels are typically slower than other citrus, but what I would do is put it on a regular fertilizer program starting the first of February and I would feed it lightly, once a month with a good balanced fertilizer and keep the nitrogen level real high. Water the trunk about once a week in the Spring and through the Summer and fertilize it lightly once a month. It should come through nicely in March.

I've got a hedge that's only about 2 feet tall, but I've noticed it's kind of sparse on the bottom and more of the leaves are on the top. Is something causing this?

-- It's usually sunlight that's causing that. Plants are naturally going to grow up and try to get as much sunlight as they can and so that bottom, which isn't getting a lot of sunlight, is going to be thinner. To keep hedges full to the ground, you're going to want to trim them with a taper, a little bit narrower at the top and wider at the base. To fertilize it you can use anything from lawn fertilizer to Miracle Grow to Citrus food, it doesn't matter, any balanced fertilizer should work just fine. Because it's not frost tender, right now would be a good time to feed them.

I have some Bamboo that has white fuzz showing up on the leaves.

--That could be a scale or a meal bug, either one. To fix that the treatment would be an insecticide. Although the easiest solution might just be to get a few new bamboo plants.

I've got some orange trees that are probably 30 years old, and I was wondering how long they will keep producing oranges?

-- If they're on sour orange root stalk, which there's a good chance they are, easily another 30 years.

I'm looking for some trees that provide some good shade for my backyard and are relatively low maintenance, what would you recommend between the Chilean Mesquite and the Arizona Ash?

-- There's a tree called an American Mesquite that's a cross between a Chilean and Arizona native Mesquite, a Texas Honey Mesquite, and an Argentine Mesquite. Why I prefer that is because Chilean Mesquites are notoriously poorly rooted trees, so they blow over and break a lot in the wind. The American Mesquite will root deeper and not break in the wind and have a lot of the same nice characteristics of the Chilean Mesquite has. The same way with Arizona Ash, but what you want to do is make sure you have a male tree with nice characteristics. You want to look for a grafted Arizona Ash variety, which would be either a Fantex Ash or a Fanwest Ash.

Is it too late to plant vegetables from seeds (November)?

-- Not at all, you can plant root vegetables like radishes or onions. You can also plant any of the leaf greens, like broccoli, cabbage, kale, or cauliflower. They should come up just fine!

I've got two Cottonwoods, how much water should I give them now?

-- This time of year (November) they will go pretty dormant and you probably just need to water them once every two weeks it's fine. Summertime the more water you give them the faster they grow, but this time of year they're going to go fairly dormant. Don't give them any fertilizer or anything because this time of year they're slowing down and they'll jump back into it next Spring.