Q: We have a mango tree (Valencia Pride) that was hit by freezing temperatures this past winter. It has lost all its leaves and appears dead. I recently did some pruning on the 12-foot-high tree in hope of stimulating new growth, but so far have seen none. I've also added citrus fertilizer and ammonium nitrate and watered with a soaker hose. Still no results. Several other similar trees in the area (not sure they are all same variety) are showing new growth. Do you think there is still any chance for this tree to survive? How long should I wait before I give up and have it removed?
Jeff Landis, Sun City Center
A: It doesn't look good for your mango. Take a pocketknife and cut into the bark halfway down the trunk and look for green. If none, continue down the trunk. If no green is found, it's time for a new tree.
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What to do about two mysterious plant pods
Q: Our pygmy date palm made it through the winter disaster seemingly okay. However, what should we do with these "seed pods" that are sprouting. Is it okay to remove them? What exactly are they?
Our foxtail, on the other hand, really got hurt by the winter. All the fronds froze and dried up. I left them for a while until I saw new ones coming out. However, the new fronds seem weak. They don't stand straight out. Could this be a sign of injury to the tree? Is there something I can give the tree for added nourishment? I have and use a palm fertilizer and also use epsom salts occasionally.
Harry and Barbara Garrabrant, St. Petersburg
A: The pods on your pygmy date, Phoenix roebelenii, are flower buds getting ready to pop. It is okay to prune them off before they open (it will save a bit of a mess) and it won't hurt the tree. Your foxtail, Wodyetia bifurcata, is still suffering from winter damage. Each frond that comes out, about one per month, will be longer, better color and less prone to breakage. Now is the time to fertilize. However, as you live in Pinellas, you are subject to fertilizer restrictions that run through Sept. 30. You are not to apply fertilizer containing nitrogen and/or phosphorous. Check with local suppliers, as they are working to create alternatives.
The best fertilizer that I have found for palms is an 8-2-12 plus loads of micronutrients and magnesium (epsom salts), developed by the University of Florida. It can be hard to find (I have only found it at Garden & Hardware in Clearwater, (727) 573-4517, and maybe Lesco in Pinellas Park, (727) 525-9008). It is a little on the expensive side, but boy it's worth every penny! It can be used on the rest of your landscape as well.
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Pesky, hungry squirrels are eating all of the hibiscus
Q: I read your column regarding bagging fruit to keep squirrels from eating them. What about hibiscus? I planted two beautiful plants that were covered with blooms ready to pop. When we returned from an evening outing, squirrels had eaten and destroyed all of them. I've read about using rubber snakes, pepper spray and even moth balls to keep them away.
Patricia Franklin, St. Petersburg
A: I have tried everything and so far nothing works. You may want to try deer or rabbit repellents. I also have heard that 1 egg mixed in 1 gallon of water sprayed on the plant repels some things - probably people! Supposedly the rotten egg smell goes away as it dries. Reapply after a rain. Keep me posted!
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Oak tree's root suckers are taking over the lawn
Q: I have two ongoing landscape problems that are getting the best of me. First, I have an oak tree that emits root suckers directly under the tree and in many areas of the yard. Under the tree and below the surface is a thick root system. The suckers are prominent, prolific and extend out maybe 20 feet. When I moved in five years ago I decided to deal with the issue by putting black garden matting over the area and reasonably thick mulch. That slowed the suckering for a while but not in the long run.
The other problem concerns a gardenia near the door. When the plant starts to bud, they fall off. The plant has a yellow tint to the leaves even though it gets watered three days per week. It seems to have a genetic defect of some kind.
Gary Miller, St. Pete Beach
A: Your sucker problem on live oak is shared by many and there is no known reason why certain oaks sucker profusely. To make matters worse, there are no repellents, hormones or chemical sprays that reliably suppress or control these suckers without injuring the mother tree. Your idea of planting a ground cover is probably your best bet. The best choice would be Asiatic jasmine, Trachelospermum asiaticum. The leaves are similar so it will blend well and the plant is as tough as the oak suckers.
As to your gardenia, hopefully your plant is grafted. The stem going down to the soil should be gray and the branches supporting the flowers should be brown. (If this is not the case, the plant will decline due to nematodes.) The reason for the yellowing is probably a pH problem. Soil in many beach areas typically has a high pH; gardenias prefer low. Check your soil and adjust accordingly. Bud drop can be caused by many factors, but a common cause is watering too much or too little. Watering three days per week is too much; one day a week is fine if the plant is established.
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Enter Greg "Dr. Hort" Charles, who educated gardeners through the Pinellas Technical Education Centers for more than 30 years. He answers questions about landscape and garden pests. E-mail your questions to firstname.lastname@example.org or to email@example.com (put Dr. Hort in the subject line). Mail questions to HomeLink, Features Department, St. Petersburg Times, P.O. Box 1121, St. Petersburg, FL 33731. Describe your problem in full, and include your name, city and contact information. If possible, include a photo. We will print his advice on Saturdays in HomeLink.