Plant Diseases

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Anthracnose

This could be a leaf spot disease called anthracnose. The usual advise is to cut the plants back to about 6 to 8 inches and force new growth, then avoid overhead watering. The natural fungicide, Bacillus subtilis (found in Bayer Advanced Natria Disease Control), is also labeled for anthracnose but it works best as a preventative, not once the disease is evident. It is very challenging to identify diseases by photo, and recommend you again get a second opinion and here are a couple of other sources to learn more:
HGIC 2204 Sweet Corn Diseases - Clemson University
www.clemson.edu/extension/hgic/.../hgic2204.htmläó_
Clemson University
Sweet corn disease problems - corn smut, rust, seed rot, seedling disease, virus, root rot, stalk rot, leaf blight, Stewart's wilt, nematodes. Disease control and ...
Sweet Corn Disease Nursery, Crop Sciences, University of ...
sweetcorn.illinois.edu/äó_
Sweet Corn Disease Nursery. 2010 Hybrid Disease Nursery Report Œ‡ Previous Annual Disease Nursery Reports Œ‡ Summary of Hybrid Reactions: 1984-2010.

Sweet Corn Diseases - Vegetable MD Online
vegetablemdonline.ppath.cornell.edu/.../SweetCorn_Li...äó_
Cornell University
Diseases By Crop (Fact Sheets) Œ‡ Photo Gallery Œ‡ News Articles/ Disease Alerts Œ‡ Diagnostic Keys ... Virus Diseases of Sweet Corn 153VCFS727.30 (1984).

By | 2017-09-11T15:49:25-07:00 January 25th, 2016|Plant Diseases|0 Comments
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Leaf Spot On Bishops Weed

This is a leaf spot - most leaf spots are caused by fungi, but a very few cases are bacterial. Without culturing in a lab it's impossible to know which fungus (or less likely, bacteria) you have but the treatment would be the same.
1) Be sure this plant isn't getting hit with water frequently. Frequent splashing of foliage with water from hand watering, an irrigation system, or drips from leaks/air conditioning/gutters is the most common thing that promotes fungal leaf spots. Water gardens deeply less often - if Mother Nature hasn't delivered an inch as measured in a rain gauge per week, water long enough to soak the area deeply (equivalent to 1" in the gauge) once a week.
2. Now that you have a problem, cut all the damaged foliage to the ground and throw it in the garbage to remove as many spores as possible.
3. After clearing out the damage, spray the area with the fungicide of your choice. If you prefer organic solutions, there are still several products available - ask at your local garden center. Treat the area once this fall and spray as the plants start to break dormancy next spring, and repeat according to the label on the product you buy. Be sure to water deeply less often next year.

By | 2016-01-25T12:18:48-08:00 January 25th, 2016|Plant Diseases|0 Comments
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Mint Rust

Yes, it appears that your mint has rust. This is a fungal problem and there are many who recommend ripping out all infected plants and replanting mint in another part of the yard far away, or planting in containers as an annual crop from now on. Others say to burn the patch to kill rust spores, but for many people this isn't practical because mint patches are often close to the house or in raised beds, and you don't want to start a fire in either of these places! Our recommendation is that you grow some mints in containers, but that you also try treating this bed with one of the newer biological fungicides that are bacteria based. These products are acceptable for organic gardening and edible crops where most fungicides are not. Two examples are Actinovate and Serenade. You would first cut down the mint that's there, and dispose of the infected plants but not in the compost. Burn them or put them in the garbage. Next mix the product according to directions and drench the soil all around the mint area and just a bit beyond. Finally, begin spraying with the product according to directions regularly as the plants begin to grow. Only water in the morning, and only water once a week.

By | 2017-09-11T15:49:26-07:00 January 25th, 2016|Plant Diseases|0 Comments
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Normal Variegation Or Nutrient Deficiency

This is not an infectious disease; its either a normal variegation that shows when leaves mature, or its possibly a nutrient deficiency and/or a watering issue. Is this a houseplant called Pothos? Its hard to ID the plant from one leaf and this particular photo, but if its a pothos then the variegation is normal for this plant. If you know for certain that its not a normal variegation then it could be a nutrient deficiency and/or a watering issue. Too much or too little water can cause plant leaves to turn yellow because the roots either drown or dry out and can't function to take in water and the mineral nutrients dissolved in the water. We would expect a much deeper yellow color with nutrient/water issues and the color in this photo appears more white than yellow. However, if you can take some of the soil in your hand and squeeze water out of it then its too wet, or if you take a handful of soil and it won't hold together in loose ball when squeezed, then its too dry. If the soil is kept evenly moist and leaves still turn yellow, then you'll want to fertilize. You can use a slow release fertilizer worked into the top 1-2 inches of soil (gently so as not to damage roots).

By | 2016-01-25T01:33:30-08:00 January 25th, 2016|Plant Diseases|0 Comments
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Rose Issues

Most likely there are a couple of diseases on your rose bush. Please keep in mind that it is impossible to diagnose diseases with certainty without proper lab testing. That being said; your rose has a case of powdery mildew and possibly either downy mildew or leaf spot. It also looks as if your bush is in the shade. The optimum environment for roses is: full sun; rich,well-draining soil; fertilizer formulated for roses; and enough water to sustain the plant. When a plant is not given its optimum growing environment, it is not able to fend off disease that it otherwise might be able to. Some preventative steps to take would be to: avoid overhead watering; remove and properly (do not compost) dispose of all affected plant parts and litter; and provide the plant with good air flow.
Here are a few links that might be helpful:
http://www.ipm.ucdavis.edu/PMG/GARDEN/PLANTS/rose.html
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7493.html
http://www.ipm.ucdavis.edu/PMG/GARDEN/PLANTS/DISEASES/downymildew.html
http://www.ipm.ucdavis.edu/PMG/GARDEN/PLANTS/DISEASES/leafspotdis.html

By | 2016-01-24T23:43:15-08:00 January 24th, 2016|Plant Diseases|0 Comments
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Golden Barrel Decline

This looks to be a combination of cultural problems, and I'm pretty sure you can't save it. The fact that it is losing the green color (and is probably getting a little soft) is a pretty good indication of root collapse and / or a fungal condition as well. Since I really don't know all of its conditions or what you have done to it besides the fertilizer, here's what you should to to keep one healthy. Regarding the fertilizer, cactus are very light feeders and really need little to none as far as food. You can feed them once a month in the hottest months of the year when they are growing (by you May through August) with an all purpose balanced food like you did, but mixed to 1/4 strength of the package instructions. Make sure that the potting mix it is in drains really well and doesn't stay soggy. When you water, water thoroughly and don't water again until the soil has become almost dry. Never let it stand in water. It should have full sun or bright light all the time as much as possible. Indoors in the winter it will be basically dormant and should still receive as much sun or light as possible, little water, maybe once a month, and no food.

By | 2016-01-24T21:22:49-08:00 January 24th, 2016|Plant Diseases|0 Comments
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Root Issues

Orchid roots should be firm to the touch. Healthy roots are often a whitish, grey, or greenish color. If they become brown or black that could be an indicator that there is a problem. Most Orchids are epiphytes and require planting in highly drainable course bark or similar. The roots need plenty of oxygen and regular moisture. Orchids can be overwatered though and will damage the roots and ultimately kill the plant if kept soggy as opposed to moist. Also the root tip can often be a different color than the rest of the roots when the plant is actively growing. This is normal and is often an indicator of growth stage and the flower color. Example: reddish to purple root tips on an Orchid will often have red to purple flowers and lighter colored root tips will be present on lighter colored flowers, etc. Roots are perishable and can be replaced with new roots given appropriate cultural care. If more than one third of the roots are dead it may be insufficient care. Many orchids are tropical and grown in greenhouses. When exposed to a new environment the roots can actually shrink and thin. It's best to acclimate the more tropical species to a new environment.

By | 2016-01-24T13:26:39-08:00 January 24th, 2016|Plant Diseases|0 Comments
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Lemon Balm Leaf Issue

Lemon Balm has very few pests or diseases. However, they can suffer root rot if overwatered. Regardless of the cause, you'll want to take several steps to prevent further problems. First, remove the damaged leaves and discard them. As a precaution, if you use clippers, wipe them with alcohol before using them on healthy leaves or plants. You may want to put some organic mulch around your plants, making sure not to allow the mulch to lay next to the plant stems. Not only does that keep any soil born organisms from splashing onto the leaves, it keeps the soil temperature even and reduces water needs. Also, water only when the plants need watering. Feel the soil before watering, making sure it's not already wet. Because all plants in the mint family will begin to droop a little when they need water, that's another good indication that it's time to water. It needs to be outdoors in full sun and the leaf damage is likely the result of chewing insects. An effective organic control against chewing insects is one formulated with Spinosad, but spray in the early evening after bees have returned to their hives. Once the spray is dry, it is safe for beneficial insects. If these measures don't improve your mint's condition, you may want to take several damaged leaf samples to a local nursery for a closer inspection to rule out any other disease process.


By | 2016-01-24T03:45:03-08:00 January 24th, 2016|Plant Diseases|0 Comments
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Problem On Salvia

This may not be an infectious disease or a pest, but we'll cover all the bases just to be sure. Examine the underside of the leaves that correspond to the black spots on the top of the leaves. If you see yellow/orange, white, or gray fuzz, or more black spots (you may need to look very closely) than you have one of several common fungal diseases. If the black spots begin to develop yellow rings around them on the top of the leaves, this is also a disease. If you see tiny little insects that are green or white you have a small infestation of a common insect. In either case, you can remove the affected leaves (it appears there are only two from your photo) and dispose of them. Then keep an eye out for further occurrances, and if you see more go to your local garden center with leaf samples sealed in a bag for advice. Otherwise, if you don't see anything on the underside of the leaves now, its likely just a single event that caused the spotting, like sunlight reflected thru an automobile window, damage caused by handling, or the plant roots dried out for a short period causing a few cells to die; and of course in this case you don't need to do anything except keep the soil moist until you plant it out in the garden.

By | 2016-01-23T03:41:34-08:00 January 23rd, 2016|Plant Diseases|0 Comments
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Sick Haworthia

Unfortunately we can't see any bugs in the photo so we might identify them as the problem, but the way the plant is shrunken and folded up looks like it might have a serious root rot going on. The only thing you can try at this point is to take it out of the pot and rinse all of the soil off the roots - look for any bug infestation too. If you don't see any pests, peel off some of the lower leaves (it looks like they are about to fall off as is) and liberally shake ground cinnamon all over the roots and lower part of the plant and set it aside somewhere out of the sun for a few days. The cinnamon is a natural anti-fungal, anti-bacterial that might help. After about 5 days get a new, not very big pot with a drainage hole in the bottom and fill with a cacti and succulent potting mix that drains well. Pot it up in the new DRY soil and set aside again for another 5 days - DO NOT WATER. After the 5 days in the dry soil it will hopefully have started some new roots and now you can give it a good drink and set it in a bright location. Don't water again until the soil has become fairly dry, say about down to your first knuckle - just stick your finger in to feel. If it did or didn't work you should be able to tell in a week or two

By | 2016-01-22T21:06:33-08:00 January 22nd, 2016|Plant Diseases|0 Comments
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