The Whitfill Garden Hour Questions

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.

November 10, 2012

What can you spray on Mistletoe to get it out of a tree?

-- The best way to get rid of mistletoe is to prune it out of the trees to a point, but you're not going to eliminate it. There is no spray to kill mistletoe and the other thing is that it's really not going to kill the tree.

We have a Fan Tex Ash and it's been in the ground for 5 years, but all of a sudden it's started to drop its leaves and the new, smaller branches are starting to split at the ends.

-- There's some sunburn on some of the Fan Tex Ash that I've seen lately. Probably your best proactive thing to do to fix that tree and make it better is to fertilize it heavy in January and get really heavy leaf growth back for the Spring. It's getting too late in the season to change anything now, but you may want to fertilize it heavy in January before it leafs out. Also, adding a little systemic rose food when you feed in February will prevent any ash aphids from growing on it.

I have a Cottonwood tree and there's some others sprouting on the lawn, they are about 3 feet high, and I was wondering if I could replant those.

-- You can definitely replant those fairly easily, even this time of year. Even better, you would probably want to wait to plant those in December of January when you're sure it's going to be cool. They're probably growing up off the roots of your main Cottonwood. Just cut a little chunk off the bottom and plant them about 8 inches deeper than they came out of the ground, with the Cottonwoods it looks very well.

How often should I water my roses now that it's getting cooler?

-- About once every week to 10 days.

I have a Mesquite tree and it's growing like crazy. When is the best time to trim the tree so it won't grow back?

-- Well, it's going to grow back and you probably don't want it to completely not grow. Here's what I would do with it, I would leave it for the Winter time because it's not going to grow anymore now. Then in the Spring, come about late April when it's really starting to grow, I would prune it pretty heavy at that time and then I would, in the meantime, look at the watering and make sure that it's only getting watered about 4 or 5 times a year, right in the heat of the Summer. Doing this will make it thrive and grow much slower.

I've got a strawberry patch and I decided to go out and give everything a light dose of fertilizer and everything in the strawberry patch has turned brown. Should I replant now or just hope that the roots are okay and that they will come back?

-- I would throw a hose on the patch and flush everything and really leech all the fertilizer out because obviously they got a little too much. Leech out the strawberry patch really well and I'd wait about a week and see if you start seeing some green poke up and down, especially with strawberries. If you don't have any success with that, then this time of year is a great time to plant strawberries.

I have a Chase Tree and it was 2 feet tall and maybe a foot and a half wide, but now, in less than a year, it is about 5 feet tall and about 5 feet wide. I want to know what I can do to keep it smaller.

-- Chase trees are very well acclimated desert trees that just love it here and if you give it enough water just to survive, it's going to grow. You can water it very sparingly, but regardless it will still grow. You can control it's size somewhat with water, but realistically if you think you're going to keep a Chase tree under 10 feet, you're probably kidding yourself.

I have a few citrus trees and a tropical bird of paradise that have some slight singing and burns from a house fire and I was wondering how to take care of them now.

-- Pretty much they should do just fine. About 2 months after the fire you should start to see some healing and new growth coming out below, it will have been long enough now that everything that is dead is kind of defined, but what I would do is prune those citrus back really hard and balance the shape out. Also, where you're going to make major cuts like 3 and 4 inch limbs, get the black tree heal and seal those limbs up. Then paint over anything that's exposed to the sun, as far as the wood goes, white to keep it from being sunburned while it recovers. Probably around the first of February you would want to fertilize on everything with a good balanced fertilizer and everything should recover pretty well. Watering also about once every two weeks should be just fine.

I've got a 25 foot pine tree and it's starting to get brown pine needles.

-- Well, lately there have been a lot of aphids and different problems. Here's what I would do, make sure it's getting a lot of water, at least once a month in the Winter, and make sure it runs really slow. The same day run the water 3 or 4 times, so you get it so the watering is really slow and really deep. You also might try a systemic fertilizer.

I have an 11 year old orange tree and all of a sudden the oranges are still hanging on the tree, but they are splitting open and then falling off. What's going on here?

-- Well, what happened was during the Summer when it was hot the tree didn't get quite enough water. Then the weather got better and you watered more and the fruit started to set and stop growing. Then as the weather started to get nicer and you watered more, the fruit started to grow again and it split. It's pretty common and nothing to really about, but to avoid it next year, you're going to want to make sure you water very consistently and deep in the Summer months. You also have to remember to adjust the water cycle for the Summer and the Winter months, the watering shouldn't be the same throughout the year.

I have a rock yard and I read somewhere that most weed killers will cause a discoloration in the rocks. Is that true?

-- Well most weed killers have dye in them, especially the pre-emergents, but they're water soluble and they leech down in the ground so the dye doesn't stay. So whenever it rains, the dye will fade and run away. It won't be a permanent stain, but there will be a temporary stain.

I've got a pine tree and it's pretty natural to the environment because I never water or take care of it and it just grows and grows. They're too high now and getting a little out of control.

-- Because you're not watering them, there's nothing much you can do other than pruning the pine tree at the top. If you prune at the top, the shape will change a little bit and that depends on the type of pine tree you have.

We have an acre that is irrigated and I heard in the past you can put sand down in the ruts, which are a couple inches deep, to level them out. Is that a good idea?

-- You can certainly put sand, but if it gets any more than a couple inches I would just use some dirt.

Is it too late to put down pre-emergent before I throw down the new grass seed?

-- No, it is not too late, but if you're going to put down grass seed, you would want to do that and ignore the pre-emergent. If you put down the pre-emergent your grass seed is not going to come up. So you would want to use the pre-emergent 3 or 4 weeks after the grass is established.

I have a multi-trunk, 6 foot Mediterranean Fan Palm, can I plant that this time of year?

-- As far as transplanting Mediterranean Fan Palms, you could transplant it now, but the best time is to wait until March or April.

I have Jalapeno peppers and the color is changing a little bit from green to red and it seems that they're getting a little bit of black on them when they're exposed to the sun. It doesn't affect the flavor, but I'm wondering if I should be concerned about that.

-- There's no reason to be concerned about that, but as they start to turn red they're the best and as they turn black they're turning a little softer and they won't be as good. When they start to turn red is when they're at their best.

We have a Hibiscus in our backyard and I noticed on one of the leaves a tiny, white bug and I was wondering if that was something we should be worried about.

-- With the temperatures changing, there's all kinds of insects that really love the warm weather, but with the temperature cooling off, that should take care of the problem. I wouldn't worry about spraying or any of that.

Is there a big difference between a Red Push Pistache and a Chinese Pistache as far as maintenance and size?

-- Well, the Red Push is very consistent so when you plant it you know what you are getting. The regular Chinese pistache is variable and the gene pool seems a little bit mixed and different, so you might have one that will be larger and one that might not be as large, it all just depends. The Chinese Pistache will have more variation than the Red Push Pistache.

I have a little orange tree in my backyard and as we left the state in the Spring there were a bunch of little buds on it, but now that we're back here in November, there isn't a bud or orange to be found.

-- Some of the oranges are going to be more alternative bearing so you'll have a light crop and then a heavy crop and that's true with all types of orange trees, including tangelos and tangerines. To have no crop, you might have had a problem with the tree getting a little dry in the hotter, Summer months.

I've got an older grapefruit tree in my backyard and it really needs to be thinned, so when is the best time to thin it? It's either got the blossoms on it or the grapefruits on it so I really never know when to trim it back.

-- Well, you can take the dead stuff out at any time and that's not going to hurt the tree at all. You also want to make sure that you don't thin a citrus tree to a point where the sun can make it through the leaves and branches and hits the wood. So you want to leave the foliage on the outside dense enough to protect from the sun and especially important in the Summer time. We do all the major pruning at our nursery in February, so that should give you a good idea.

What kind of blooming flowers can I have on a second-story deck with a very slight bit of sunshine in the late afternoon?

-- Probably not too much, but my favorite plant though for there would be cyclamen. They have beautiful colors and you can put it out there in a pot this time of year and bloom and stay that way until May.