Plant Diseases

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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.

Fungal diseases are something all northeast gardeners dance with when growing tomatoes - given the treatments above, however, there is no reason you can't grow tasty, organic tomatoes all summer until hard frost. A freshly picked tomato is worth all our efforts.

By | 2015-12-02T19:28:48-08:00 December 2nd, 2015|Plant Diseases|0 Comments
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Fungal Problem On Peppers

You have one of the fungal diseases that can affect vegetables. Without culturing in a lab it's impossible to say for sure which one this is, but the treatment and prevention for the home gardener is the same.
Note that many fungal conditions can be worse when nights are cool since moisture condenses onto plants (dew) and keeps them damp overnight. It's been a cool summer in the northeast, and peppers like it hot, hot, hot! So it's only natural that there may be more leaf spot and fruit rot problems in a season where the nights are cool.
1. Be sure not to water in the evening and try not to get the fruit wet when watering when possible. Water deeply less often - don't hand water because that will lead to the necessity of watering frequently. Soaking the garden with a soaker hose or sprinkler for a long time every 5 days is better than shallow watering less often, since watering frequently is likely to get the fruit wet.
2. Spay with one of the organic fungicides such as Actinovate, Serenade or copper. Ask for an organic fungicide at your garden center and use it according to directions. Be sure to spray the leaves, developing fruit and stems. Next season start to spray your pepper plants early, before they get the problem since it's easier to prevent fungal problems than it is to treat them once they have arrived.
3. Throw out infected fruit - don't let it stay in the garden. Once the pepper plants have stopped bearing pull them and toss them out or burn them too - don't add to the compost pile.

By | 2017-09-11T15:49:32-07:00 December 2nd, 2015|Plant Diseases|0 Comments
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What Fertilizer Did You Use

I see that the foliage is looking a bit yellow and that there is some browning on the edge of a couple of the leaves. Did you use an organic fertilizer or a synthetic one such as one of the "blue liquids?" If you used a synthetic and used a bit too much you might be seeing signs of fertilizer burn. If you used an organic product it wouldn't be fertilizer burn.

It's possible that the yellowing is just some of the leaves shutting down as peonies can do at this time of year. Are all the leaves looking like this or just the older ones? Has the plant been watered deeply once a week through the summer? In general peonies need one inch of rainfall (measured in a rain gauge not a carton or cup) over a 24 hour period, once a week. If the plant hasn't gotten that much water it might just be starting to go into "fall mode" a bit early.

In general this isn't a great time of year to fertilize peonies (or other perennials) in that the time when they put on their growth is in the spring and early summer. Right now perennials are stockpiling carbohydrates that they will use for winter survival, and they use the growth that was created in the spring to do this.

Additionally, the blackening you see might be fungal in origin - it's natural to see some signs of leaf spot fungi at this time of year and this year more plants are showing fungal issues because of the cool night temperatures.

The best thing for you to do at this point is to make sure the plant gets deeply watered once a week. A light application of composted manure on the top of the soil is always a good idea for plants as well.

If the leaves continue to yellow and turn brown, and you used a synthetic fertilizer, soak the soil well today to flush some of it away and hope for the best. In the future fertilize these plants with an organic such as Flower-tone applied in the early spring.

By | 2015-12-01T22:37:47-08:00 December 1st, 2015|Plant Diseases|0 Comments
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Powdery Mildew On Zucchini

It is probably powdery mildew. This fungus is common to squashes (and cucumbers, which are in the same family), especially if the foliage is wet at night. Drier weather will help, but if many leaves are affected, fungicide sprays will arrest its progress and allow you to harvest.
Trim off the damaged leaves. There are several organic fungicides that are labeled for powdery mildew including Actinovate, Serenade, sulfur, and Green Cure, or ask at your local garden center. Be sure to spray under the leaves and the stems as well.

The warm days and cool nights of late summer create an ideal climate for spore growth and dispersal.

Powdery mildew can be prevented, and it can be controlled once it appears, but it can't be cured. The key to preventing it is planting mildew-resistant or mildew- tolerant varieties. Resistant varieties get less mildew than susceptible varieties; tolerant varieties may get some mildew, but it shouldn't affect the performance of the plant. Prevention also includes siting plants where they will have good air circulation, and exposing as much leaf surface as possible to direct sunlight, which inhibits spore germination.

Other methods of coping with it: pick off affected plant parts and either compost them in a hot compost pile or bag them tightly and put them in the trash. Or create a spray of 1 part milk with 9 parts water and spray the stems and tops of leaves with the solution. Reapply after rain.

By | 2017-09-11T15:49:32-07:00 December 1st, 2015|Plant Diseases|0 Comments
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Stretched Echeveria

You have an Echeveria that is really suffering because of poor conditions. It is stretching and losing its color because it is not getting enough light - It looks like it is also way overwatered. It's difficult to bring them back to normal at this stage so here's what you can do - bare with me! First, stop watering. The very lowest leaves are goners so just pull off and toss. Take a look at the overall length of the stem from soil level up to the top. Cut the head of the plant off about half way up that stem. It should leave you with a stem in the pot with a few large leaves attached, and the decapitated rosette in your hand. Move the pot with the original stem to an area that receives very bright light, even a bit of direct morning sun. Don't water that pot again until the soil has become fairly dry. When it has, you can water again. This is the way you typically want to water succulents, letting the soil dry out a bit before watering again. With any luck, in a few weeks you should see some tiny new rosettes forming on that old stem and you're home free. It should grow as a multi-rosette plant, and if you keep it in the brightest, slightly sunny spot you have, it should color up, grow more compact and rose-like. Now for the heat you have left over, remove a few of the larger lower leaves and save them, giving your rosette just a little stub of a stem on the bottom. Stick it and the few saved leaves and put them on a paper plate and put them somewhere out of the way for about a week so they can callus over their cuts - I usually stick them on top of the refrigerator so I don't forget them. after the week, prepare two small new pots with new potting mix that drains well. Gently just snuggle the little stub of the rosette into the soil of one pot, and lay the leaves on the soil of the other pot with their skinny ends just touching the soil - they sometimes do this easier if you lay them upside down. Now, for both pots, back on the fridge or wherever, out of the sun, and no water - just dry soil. Leave about another week or so and by then you should start to see new roots on the leaves and the same thing should be happening on the rosette stem. NOW give them a good drink and move them to the brightest location - avoid full sun for a while until they get going. Water them as I had mentioned before allowing the soil to dry out slightly before watering again. If the Plant Gods are with us, you will wind up with at least one healthy plant to start with again, but likely you'll have several plants after awhile - GOOD LUCK!

By | 2015-12-01T05:18:44-08:00 December 1st, 2015|Plant Diseases|0 Comments
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Epinasty Of Tomato

We're not sure from your photo what problem you are indicating, but it does appear that the leaf petioles (leaf stems) are turning downward. If this is not the problem you are indicating, please send us a new photo with a close-up of the problem you would like us to look at, and we'll send another response. Otherwise, this downward turning appears to be an abiotic, non-infectious, disorder called Epinasty. This can be caused by various things, but since you're applying so much water so often, this is very likely the result of anaerobic soil conditions, in which the soil holds too much water and not enough oxygen for the roots to function properly. With the amount of water your applying daily, oxygen is not likely available in your soil. This can cause plants to produce a gaseous hormone called Ethylene, which is the actual cause of the downward turning of the petioles/stems. We've included a quote from the Plant Physiology Journal, as well as the link to this article for your reference. We recommend that you cut back on your water applications, and only water to keep the soil evenly moist. As you say, weather conditions may dictate more water during some weeks, and less during others. A moisture meter may be a good tool to use. You can get these at many garden centers. Tomatoes like deep watering, fewer times per week. This downward turning cannot be corrected, but you can still get the plant to produce, if proper care is provided. We've also included a link (the last one below) with some information from the UC for your reference.
From: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1091906/
"....... results indicate that deprivation of O2 to the roots is the primary effect of soil flooding, and that this is sufficient to cause increased ethylene synthesis in the shoot."
Tomato care at this link..... http://www.ipm.ucdavis.edu/PMG/GARDEN/VEGES/tomato.html

By | 2015-11-30T19:40:30-08:00 November 30th, 2015|Plant Diseases|0 Comments
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Septoria Leaf Spot Or Early Blight

This could be septoria leaf spot but it could also be Early Blight. Both are fungal. Early blight typically starts at the bottom of the plant and works up. Both are fungal. Septoria leaf spot usually begins in damp, cool weather and one strategy to beat it is to plant your tomatoes LATER in the season when it's warmer. Even if you solorize your soil you won't get rid of either of these. You must learn to cope with them as follows.

The way we "dance with tomato fungi" is this: When planting, remove any leaves that touch the soil so that the only place the plant makes contact with dirt is at the stem. Mulch around the plants immediately with the mulching material of your choice. That is immediately after planting so that any spores in the soil won't be able to get splashed on your plants when you water or it rains. Spray weekly with one of the bacteria-based, organic fungicides. Ask at your local garden center to see which ones they carry. Use these every week according to directions. Pick off the worst of the spotted leaves as they happen and throw away. Don't let any dropped foliage or fruit remain in the garden. Water only in the morning and deeply less often - watering every four or five days deeply will allow the foliage to be dry most of the time.

The most early blight resistant varieties are Mountain Magic and Mountain Merit. Heirloom tomatoes always get diseased before hybrids, so look for hybrid plants.

By | 2015-11-29T02:34:48-08:00 November 29th, 2015|Plant Diseases|0 Comments
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Euonymous Branch Demise

Your bush looks like a Euonymous, an evergreen bush common in your area, but we can't be sure without a close up of the leaves. Regardless of the type of bush it is, it clearly has suffered damage to several branches, either from mechanical injury, a disease process, or from some type of critter.

We recommend removing the dead branches as far as they extend into the base of the shrub. You'll want to closely inspect both the damaged branches and the soil around the base of the shrub to try to determine what may have caused the branches to die.

Individual branches on any plant can suffer and even die from the weight of heavy snow. Often the damage isn't seen until mid-late spring. Look for bent and splintered branches.

Also look for signs of critter damage such as nests, chewing marks on the dead branches, etc., so you can deal with the offending critter(s) before more branch damage occurs. Sometimes voles, small field mice, get into these shrubs and chew the outer layer of the branches, cutting off the water supply. They leave trails or furrows in the soil at the base of the plant. You'll want to contact your local extension agency for control information if you see critter damage. Here's a link to their website - http://extension.usu.edu/saltlake/

If you don't see evidence of the above, check the dead branches for swollen areas called galls. These are present when an insect or bacteria has entered the branch. They also cut off water supply to the branch. Here's a link to a website with more information, including pictures of galls, so you'll know what to look for - http://www.clemson.edu/extension/hgic/pests/plant_pests/shrubs/hgic2054.html
If you find galls, remove the branch, including the portion with the gall. Whatever tools you use to remove the dead branches, don't use those tools on any other plants, including this one, until you have sanitized them by wiping them with rubbing alcohol in case their is a disease process that could be spread to other plants via your pruners.

Your decision as to whether to remove just the affected branches and wait for regrowth or remove the entire shrub is somewhat based on determining the source of the damage. If it's bacterial, resulting in galls, the same infection can occur on a new similar shrub. If all of this seems overwhelming and a lot of work, you can simply remove an affected branch back to the base of the shrub and take to a local nursery or to your extension agency for a more thorough examination and suggestions on removing the entire shrub vs removing just the affected branches.

By | 2015-11-28T06:27:54-08:00 November 28th, 2015|Plant Diseases|0 Comments
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Powdery Mildew On Zucchini

This may be environmental damage. Leaf spot such as you see can be caused by something physically hitting the plant, a fungus, or a bacteria. A physical cause would be something such as hot water from a sun-heated hose, a cleaning product such as window cleaner, a fertilizer spray or drift from an herbicide or other garden product. If this is the cause the damage doesn't spread and there is no threat to the plant.

However, if you see it spreading and getting worse, it is probably powdery mildew. This fungus is common to squashes, especially if the foliage is wet at night. Drier weather will help, but if many leaves are affected, fungicide sprays will arrest its progress and allow you to harvest.
Trim off the damaged leaves. There are several organic fungicides that are labeled for powdery mildew including Actinovate, Serenade, sulfur, and Green Cure, or ask at your local garden center. Be sure to spray under the leaves and the stems as well.

The warm days and cool nights of late summer create an ideal climate for spore growth and dispersal.

Powdery mildew can be prevented, and it can be controlled once it appears, but it can't be cured. The key to preventing it is planting mildew-resistant or mildew- tolerant varieties. Resistant varieties get less mildew than susceptible varieties; tolerant varieties may get some mildew, but it shouldn't affect the performance of the plant. Prevention also includes siting plants where they will have good air circulation, and exposing as much leaf surface as possible to direct sunlight, which inhibits spore germination.

Other methods of coping with it: pick off affected plant parts and either compost them in a hot compost pile or bag them tightly and put them in the trash. Or create a spray of 1 part milk with 9 parts water and spray the stems and tops of leaves with the solution. Reapply after rain.

By | 2017-09-11T15:49:33-07:00 November 27th, 2015|Plant Diseases|0 Comments
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Bacterial Leaf Spot Early Blight Or Other Fungal Issues Tomatoes

From the leaf alone we can't tell if this is a bacterial or fungal problem. There are several tomato leaf diseases that look similar and the only way to tell for sure is to have the leaves cultured in a lab. That said, for the home gardener the treatment would be the same. Since fungal problems are FAR more common than bacterial problems in the northeast, it makes sense to treat this as if it is a fungus. If it's bacterial the problem will rapidly continue and there's nothing you can do, but if it's fungal you can slow the spread so you'll still get tomatoes so what have you got to lose?

Start spraying now with an organic fungicide. Early in the season, before the plant has a problem the products of choice are the biological fungicides such as Actinovate and Serenade. But once a plant has a problem you should go right to the "heavy hitter" of organic fungicides, copper. Ask at your local garden center for a copper fungicide and use it according to directions. Most people find that a weekly application of copper will halt or slow an infection enough to allow the ripening of fruit for three to eight weeks.

Be sure to put the foliage of these plants into the garbage or the burn pile, not into the compost. Next year start spraying your plants regularly with Actinovate or Serenade from planting on...it's easier to stall the problem than it is to treat it once the plant is infected.

Also, be sure to water your plants in the morning only and try not to get the foliage wet when you do so. Frequently sprinkling the foliage with water is a prescription for leaf spot diseases. Water deeply less often.

This summer's cool weather has contributed to tomato leaf and fruit diseases.

By | 2015-11-13T20:36:48-08:00 November 26th, 2015|Plant Diseases|0 Comments
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