Plant Diseases

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Leaf Spot On Succulent

There is good news and bad news here. The good news is that you have babies from this plant, and with succulents such as this you can always cut off the tippy top growth and stick the stem in a new pot of soil to start a new plant. The bad news is that you do have some sort of leaf spot disease - probably fungal - and those leaves are likely to fall off soon.

The other good news is that if this plant is 6 feet tall you're probably ready to start fresh and not have to duck every time you water it, right?

Even houseplants have a life-span or shelf-life. Once they get really tall and leggy, they are often not as attractive and since they are taller they aren't as healthy since they aren't getting the benefits of full sun through most windows. At this point, start with a new or recently cleaned pot, all fresh soil (a cactus mix is good for succulents) and cut the top off of the tall mother plant. Remove all the spotted leaves and poke about 4 inches of the stem down into the fresh soil. Water the plant well but after that don't keep the soil wet or the stem will rot. A good watering once a week should be fine even while the plant develops new roots. You can pot up the "babies" on either side of this newly short plant in order to make an attractive, fuller new succulent.

Leaf spots are common on most plants - you can spray the plant with a sulfur fungicide and always avoid getting succulent foliage wet. (Ignore all the advice you see on line to "mist" your plants.) Sometimes plants are more prone to problems if they aren't as healthy or strong to begin with due to being in the same pot and soil for a few years. That's another reason it's good to start fresh!

By | 2015-11-13T20:37:26-08:00 December 7th, 2015|Plant Diseases|0 Comments
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Septoria Leaf Spot

This is Septoria leaf spot. The wet weather we have had this spring has contributed to it's rise in gardens this year. First, remove all the affected leaves and place in the trash not the compost pile. Next year rotate your tomatoes because the fungus will over winter in the garden for a season and would affect next years crop. This is specific to tomatoes not cucumber or the like. Good air circulation is very important when planting. Sterilize all your garden equipment that comes in contact with the tomatoes so it doesn't spread. Mulch your tomatoes if you haven't already. It keeps the spores from splashing on the ground and spreading the disease. If the above measures do not control the disease, you may want to use fungicidal sprays. Fungicides will not cure infected leaves, but they will protect new leaves from becoming infected. Apply at 7 to 10 day intervals throughout the season. Apply chlorothalonil, maneb, macozeb, or a copper-based fungicide, such as Bordeaux mixture, copper hydroxide, copper sulfate, or copper oxychloride sulfate. Follow harvest restrictions listed on the pesticide label. You can also use Serenade, an organic fungicide that I personally use. When spraying the plants, make sure you spray the undersides of the leaf as well. Since you are in Morningside (there is a geo locator that comes with your request so it goes to right area advisors and I have friends there) I'm going to assume that your garden is probably in close proximity to your neighbors gardens as well so they may want to keep an eye on their garden as well.

By | 2017-09-11T15:49:30-07:00 December 6th, 2015|Plant Diseases|0 Comments
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Seed Starting Issues

There is a fungal disease term called "damping off" disease and it affects seedlings. It actually is several diseases such as phytophera or thielivalopsis that kill the seedlings. I am a professional greenhouse grower and I don't like using those paper pots because they sometimes contain lead ink. They also wick away moisture from the potting mixture causing them to dry out. If you go to your local garden center you can purchase a seed starting kit. It will contain all you need to get started. From the photo, I don't see a lot of light for the plants. I would suggest a grow light fixture about 6 inches above the plants to give them a healthy start. Once they start to grow you can shorten up the light. You should also have good air circulation between plants to reduce disease transmission. Disinfect everything with a solution of 1 part liquid bleach to 9 parts of water to make a 10% disinfecting solution.
Watering when the soil is dry is important. Don't mist plants. It causes the foliage to stay wet and fungal spores to take hold. Just gently but thoroughly water the seeds/seedlings. There are two other thoughts I have about your problem without seeing it in person. The first is you could have contaminated potting mix although that is very unlikely. The other could be that you are not watering the seedling thoroughly and the roots aren't getting the water, only the top of the plant is getting water. Hope this helps and don't give up gardening!

By | 2017-09-11T15:49:31-07:00 December 5th, 2015|Plant Diseases|0 Comments
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Septoria Leaf Spot

It's either early blight or one of the leaf diseases - there are two for tomatoes, Septoria (tends to be smaller spots) and bacterial spot. If the yellowing goes from the bottom of the plant up, that argues for early blight. Without culturing in a lab it's hard to say which it is but the treatment for the home gardener is the same:
1. Pull off the leaves that are spotted and yellow so the plant can be better monitored and some of the spores are removed.
2. Never get the foliage wet when watering. (It's amazing how many people routinely spray the leaves of plants every evening because they think that they are somehow "refreshing" the plant. This is a prescription for every leaf disease in the book.) Water deeply less often.
3. Start spraying immediately with a copper fungicide - this is an organic treatment that is a bit stronger than other organic fungicides. If the garden is right next to a pond, lake or stream, however, do not use copper as it is toxic to aquatic life. (In such cases I would use Actinovate, a natural bacteria.) Spray under the leaves and the stems too. Although the fungicide won't "cure" the problem it can protect the newer growth long enough so that tomatoes can be harvested. Next season start spraying early first using something like Actinovate or Seranade, and switching to the copper once the plant has a problem. (Do not alternate these - the copper will kill the bacteria in the other two products.)

By | 2015-12-05T09:58:58-08:00 December 5th, 2015|Plant Diseases|0 Comments
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Leaf Spot On Tomato

Your leaf spot could be a couple of different fungal problems and without culturing in a lab it's impossible to say which one you have. This might be septoria leaf spot, or it could be the beginnings of early blight, or another fungus - but the response to all three is the same.
1. When you water be sure to water deeply less often, and not to get the foliage wet if you can help it. Watering with soaker hoses is a good way to water tomatoes. Avoid watering in the evening so that the foliage stays wet all night - water in the morning if you are using sprinklers, and water every four to six days instead of every other day, for example.
2. Pick off the worst of the spotted leaves and throw them out. In future years be on the lookout and start removing spotted foliage early.
3. Start spraying with one of the organic fungicides such as Actinovate, sulfur or copper. Use according to directions. This won't "cure" the problem but can protect undamaged foliage and fruit until frost. In future years start spraying before plants have a problem and spray regularly according to the directions on the label.
4. Since most fungi are air born AND overwinter in the soil, mulch around your newly planted tomatoes as soon as they are planted to prevent spores from splashing from the ground to the plants in future years. There is no soil treatment you can use to kill harmful fungi that doesn't also kill the beneficial fungi, so don't consider treating the soil with fungicides - they don't work.
5. When you clear out the garden this fall either throw out the old tomato foliage and old fruit or burn it - don't leave it in the garden over the winter.

By | 2015-11-13T20:51:36-08:00 December 5th, 2015|Plant Diseases|0 Comments
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Artillery Fungus

The artillery fungus, Sphaerobolus spp. may become problematic in mulch, due to the production and release of its spores. This fungus produces very small, inconspicuous cup shaped fruiting bodies (about 1/10 of an inch) that contain a dark round spore body (peridiole). The accumulation of water and nutrients in the fruiting body eventually leads to a pressure release of the spore. That spore is shot toward any light source up to a distance of several feet. With windy conditions, spores can travel even further. When they land on light colored siding, building foundations, or cars, the material can be very unsightly. The spore bodies have a very sticky substance on them which can make removal extremely difficult. Soap and water with a scrub brush can be effective, before the material gets dry. Increased reports of artillery fungus causing problems may be due to use of hardwoods in mulch, excessive rainfall, or irrigation of foundation plantings. Artillery fungus may be more problematic on the north side of buildings where shade maintains more moist conditions. The use of bark mulch or pine bark nuggets rather than hardwood may provide a less favorable substrate than hardwood mulch for artillery fungus. Use of mulch derived from trimming of dead and diseased trees should be avoided. Adding fresh mulch yearly can also suppress the fungus, but plantings should not be mulched too deep. Removal or raking of infested mulch to disturb the growth of the fungus may help. Dr. Don Davis of Penn State University has a web site with more information and answers to frequently asked questions: http://www.personal.psu.edu/faculty/d/d/ddd2. Dr. Davis and his colleagues have done recent research indicating that the use of fresh mushroom compost blended with landscape mulch, at the rate of ≥40%, can be effective in reducing or suppressing the artillery fungus. This can be a good strategy in sites that have had problem with artillery fungus previously. Addition of the fresh mushroom compost adds organic matter, a rich dark color, and beneficial microbes that may compete with the artillery fungus offering some control. For more information, see the UD Plant Clinic Web site: http://extension.udel.edu/ag/plant-diseases/ud-plant-diagnostic-clinic/ or contact your County Extension Office.

By | 2017-09-11T15:49:31-07:00 December 5th, 2015|Plant Diseases|0 Comments
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Lear Spot On Melon

This is a fungal leaf spot. Without culturing in a lab it's impossible to say which fungi is causing the problem, but since the treatment is the same it really doesn't matter which one it is. Here's what you need to know:
1. Leaf spot occurs on most plants to some degree. The longer the season, the more it shows up, so it's common to find it later in the summer or in the fall.
2. Frequent splashing or dampening of foliage can lead to leaf spot on most veggie plants. For this reason be sure not to get foliage wet when you water - don't water in the evening if you can help it, so the leaves won't stay wet all night. Direct water at the soil not onto leaves. (In seasons when days are warm and nights are cool there is more dew on the plants naturally, so cool night temperatures are pretty much a prescription for leaf spot fungi.)
3. It's common to see more leaf spot on older leaves since they've been around longer. As soon as you see spots and yellowing leaves, clip these off and throw them away.
4. You can help protect undamaged foliage by using an organic fungicide. There are several available including Serenade, Actinovate, copper and sulfur. Ask at your local garden center for an organic fungicide labeled for fungal problems on vegetables, and use according to directions in terms of concentration and frequency.
5. It's always easier to protect undamaged foliage than it is to treat infections that are already underway - so in future years start using an organic fungicide BEFORE the plant gets a problem - use according to label directions.

By | 2017-09-11T15:49:31-07:00 December 5th, 2015|Plant Diseases|0 Comments
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Houseplant Leaf Drop

There are numerous reasons for houseplants to drop leaves. Without our staff being there in person to touch the soil and plant we are not able to specifically say what is causing your leaf drop. Houseplants typically drop leaves for many reasons but most are related to improper care or poor growing conditions. What are some of these reasons? Either too much or too little watering will cause leaf drop. Extremely low humidity will cause sensitive plants, such as gardenia, to drop leaves although most common houseplants will not show leaf drop in response to low humidity only. Plants in pots that are too small will drop leaves. Why? Because there may not be enough root room to support all the leaves the plant tries to form so the oldest leaves drop off. Because the space for the roots is inadequate, the plant may not be able to absorb enough water and nutrients. Some leaf drop occurs when plants are subjected to a big change in environment. Such changes occur when plants grown outside for the summer are brought inside for the winter. Leaf drop brought on by a change in environment should last about three weeks then stop. Chilling is one cause of leaf drop related to environment. Tropical plants are sensitive to low, but above freezing, temperatures. Plants on windowsills may be exposed to chilling temperatures. Hot or cold drafts may be a problem for some plants. Insects and diseases can cause leaf drop but are not as common as the previously listed causes. Some leaf drop on houseplants is normal. The solution may be simple. It may just need more light or fertilizer.

By | 2017-09-11T15:49:32-07:00 December 4th, 2015|Plant Diseases|1 Comment
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Petunia Problems

We think that there are several issues with your petunia. 1. It looks like it needs fertilizer. Has it been fertilized since you bought it? Petunias need either a good application of a time-release fertilizer in June or every other week liquid fertilizer used according to directions. 2. This plant looks like it needs deadheading as well. Regular petunias (not Supertunias or Wave Petunias) need to have the developing seeds that are under the wilted flowers snipped off in order to keep blooming. 3. Brown leaves. This is most likely from the plant drying out in between waterings, although splashing of the foliage with water can also cause such browning. This might be a combination of both. Since this plant is growing in such a small pot it's hard to keep it constantly moist so that can cause browning, and since the foliage is so thick it's hard to water without getting the leave wet! In general, water such containers well in the morning, tucking the hose or can just over the rim so that the water runs into the pot but not on the leaves. Then do it again later in the day, depending on the weather. In hot weather a small basket will need watering twice a day - if the temperatures are cooler you can do it once a day.

In the future, look for a hanging basket that has a larger pot - yes, they are more expensive, but they don't dry out as quickly and the plants don't get crowded as fast. Mandevilla vines are easy, as is Scaevola and ivy or alpine geraniums.

By | 2015-12-04T08:01:11-08:00 December 4th, 2015|Plant Diseases|2 Comments
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Diy Disaster

From this photo, I can't really tell what the plant used to be but you definitely did some damage. For starters, you should always make sure if you are going to spray a plant for anything, it should be watered at least 12 hours before spraying. In the picture I can see that the plants aren't getting enough air circulation, important to reduce the chances of disease and insects. I never ever recommend home concoctions since their efficacy can vary widely. You didn't specify what oil you used, if it was a vegetable or hort oil. If you used a vegetable oil, you have effectively smothered the plant.(s) stomata which helps respiration. In homemade concoctions, the only two detergents ever recommended are Ivory soap and Dawn dish detergent. Others contain ingredients such as orange or lemon oil which is fine for dishes, not so much for plants. About the only thing I can I can suggest now is to cut back the plants hard and see if you get some new growth at the base.. You should separate them and place them in a cooler, brighter area. Plants don't need to be as warm as you and it helps reduce insect problems. Do not fertilize as that will produce soft green growth, perfect for aphids. Bringing herbs indoors does invite problems so you have to be careful when doing so. Since aphids prefer new growth, you should check at least once a week for an infestation. In the future, use a product registered for using on herbs indoors and not a homemade concoction.

By | 2017-09-11T15:49:32-07:00 December 4th, 2015|Plant Diseases|0 Comments
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