Plant Diseases

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Leaf Spot On Bearded Iris

The yellow halos around the brown centers indicate a fungus disease. It is necessary to treat the iris with a fungicide to arrest it, but that will not solve the issue. Leaf diseases weaken them and that affects the next year's flowers. Shade, crowded plantings, rainy weather, and mulch or soil covering the rhizomes increases the chances the disease will take hold as it has here. Suggest you dig up the iris clumps, trim their leaves into 6" fans, divide them, and replant farther apart. If it's been a few years, you'll want to amend the bed to assure good drainage and drench it with fungicide before you replant. For the next year, spray new growth with a fungicide to inoculate it against more development. After that, watch for it and spray at the first sign of spots.

By | 2016-03-22T10:00:31-07:00 March 22nd, 2016|Plant Diseases|0 Comments
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Bromeliad Death

We're sorry to say... No, this Bromeliad plant cannot be saved. It has either died naturally (after flowering once these plants die, sometimes producing a new "pup" or baby plant at the base of the stem before dieing), or it has been over-watered and the stem rotted. These plants don't live in soil in their native habitat, although they are commonly produced that way in greenhouses, so this make it easy to over-water them. They usually only need a little water inside the center "cup" formed by their leaves, and then just enough water in the soil to give the pot weight and hold it upright. Next time you have one you can look up the watering techniques used to keep them from getting too much water. They are very different from our usual houseplants.

By | 2016-03-22T06:49:50-07:00 March 22nd, 2016|Plant Diseases|0 Comments
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Bacterial Leaf Spot Or Tomato Leaf Spot

This looks like its probably a leaf spot disease, either Bacterial or fungal Septoria leaf spot; both of them are spread by splashing water on leaves. We've included some web links about them for your reference, but the only way to ID plant disease for certain is to have a pathologist test the tissue. You can take samples of all affected plant parts (sealed in a bag) to your local Dept of Agriculture office and they will reply to you by mail for free. Provide them with as much info about the plant environment as possible. In the meantime, you may choose to remove the most affected leaves, and we recommend you review the info provided in the weblink about caring for tomato plants.
http://www.ipm.ucdavis.edu/PMG/GARDEN/VEGES/tomato.html

By | 2016-03-22T03:56:29-07:00 March 22nd, 2016|Plant Diseases|0 Comments
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Phyllosticta Leaf Spot

It is very difficult to identify a disease from a photograph, but your problem may be due to a fungus that begins with irregular, roundish, yellow-brown spots or lesions and as the disease progresses will form black target-like spots in the center. Fungal spores are spread by wet weather when leaves are splashed by the spores. Remove and destroy affected leaves including the foliage that has fallen to the ground, do not water overhead, but instead at the base of the plant, water regularly.Suggest you take a leaf sample to your local garden center for confirmation and if it is, unless the fungus is widespread, it should not harm the tree, but if it is widespread, eventually this will weaken it. A copper fungicide may be the appropriate treatment for control.

By | 2017-09-11T15:49:18-07:00 March 22nd, 2016|Plant Diseases|0 Comments
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Mealybugs

Your photo is distant and we cannot make out the details of these insects clearly. If these insects have a cottony, fuzzy and sticky feel to them, it is likely your infestation is mealybugs. Mealybugs suck the nutrients out of the plant and will eventually kill it if left untreated. Consult your local garden center for confirmation of the problem and remedies. If they are mealybugs, you can hand remove them with a cotton swab dipped in alcohol and then rinsed off, but if the infestation is extensive, you may want to wash them off with a strong stream of water, followed by a spray with insecticidal soap or pyrethrin product. There are also chemical controls formulated with imidacloprid, but make sure it is formulated for citrus.

By | 2016-03-21T16:35:54-07:00 March 21st, 2016|Plant Diseases|0 Comments
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Dog Vomit Fungus

Fuligo septica is a species of slime mold. It is commonly known as the dog vomit slime mold or scrambled egg slime because of its peculiar yellowish, bile-colored appearance. A common species with a worldwide distribution, it is often found on bark mulch or in lawns in urban areas after heavy rain or excessive watering. Their spores are spread by wind. To remove the mold, be sure to dig it while it still looks like vomit. Once it powders and spreads, you can get a giant mold problem in the garden. Dig out the mold entirely and throw it out. Do not burn it. Do not compost it. Then wash all the tools and gloves you used with a weak bleach mixture as it can recontaminate your yard later. Be sure to cut back on the watering of the lawn for a while. Best of luck!

By | 2016-03-19T23:24:15-07:00 March 19th, 2016|Plant Diseases|10 Comments
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Botrytis On Orchid

This looks like Botrytis, or gray mold; if not exactly that, it is a fungus of some type, likely caused by high humidity and little to no air circulation in the box - a perfect environment for fungal growth. The best thing you can do is let the fungus dry out as much as possible, provide good air circulation, make sure the orchid is potted in a very well drained media (bark is very good for this, and while you're transplanting, you can remove infected tissues as much as possible), and provide appropriate light exposure for the plant. The fungal spores may re-generate if conditions are right for it, but if you care for the orchids properly it shouldn't be an on-going problem. Here's a link about the fungs:
http://www.ipm.ucdavis.edu/PMG/r280100511.html

By | 2016-03-19T12:33:03-07:00 March 19th, 2016|Plant Diseases|0 Comments
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Cherry Leaf Spot

Your tree may have cherry leaf spot, caused by the fungus Blumeriella jaapii. Cherry leaf spot targets the foliage of cherry trees but can also infect stems and fruit. Small purple spots on the tops of leaves are generally the first symptom of this fungal disease. The spots turn brown and begin to enlarge and collapse, leaving a hole in the foliage. Older leaves will yellow and drop from the branches, and the cherry tree can lose all its leaves, which weakens the fruit tree and increases its susceptibility to cold damage.

Properly timed applications of fungicide will help prevent cherry leaf spot. Start fungicide preventive sprays at the petal fall stage and repeat every seven days until harvest.

You may want to get a second opinion and take sample to local nursery for confirmation.

By | 2016-03-18T16:33:08-07:00 March 18th, 2016|Plant Diseases|0 Comments
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Spirea

Cylindrosporium Leaf Spot

Spirea leaves with both surfaces exhibiting light-yellow lesions that darken over time suffer from Cylindrosporium filipendula leaf spot. Inspecting their undersides reveals yellowish, waxy spore masses. On heavily infected plants, the tiny, round leaf spots merge into large dead patches. Extensive summer leaf drop may follow. Splashing water spreads Cylindrosporium spores from leaf litter and contaminated plants.
Leaf Spot Control
Spireas tolerate mild leaf spot with no serious damage. Removing infected leaves and debris eliminates the spores they harbor. Watering the shrubs from beneath in the morning minimizes foliage moisture, reducing the risk of infection. Cylindrosporium seldom requires fungicidal treatment.

By | 2016-03-18T08:45:34-07:00 March 18th, 2016|Plant Diseases|0 Comments
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Tobacco Mosaic Virus On Tomato

It may be that your tomato plant has Tobacco Mosaic Virus (TMV). The "mosaic" appearance of the yellow/green tissues of the leaf, and what appears to be a "shoe-string" look (to a few of the leaves, but its really not very clear) is a characteristic symptom of this virus disease. Unfortunately viruses cannot be reversed or cured, however infected plants may produce edible fruit, but yield, size, and quality are reduced. We've included this link for your review. TMV is very easily transmitted when an infected leaf rubs against a leaf of a healthy plant, by contaminated tools, and occasionally by workers whose hands become contaminated with TMV after smoking cigarettes. We've included a web link with more info.
http://www.ipm.ucdavis.edu/PMG/GARDEN/VEGES/DISEASES/tobaccomosvir.html

By | 2016-03-18T03:20:45-07:00 March 18th, 2016|Plant Diseases|0 Comments
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