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Passionflower winter care

I have a passion flower that I brought in for the winter. It has lost all leaves and has sticky little brown spots on it . How do I get rid of the brown sticky things? And how do I get the leaves to grow back. Would putting under a grow light for the winter help.

 

I read up on Passionflower cultivation and pests in the book Passiflora: Passionflowers of the World by Torsten Ulmer & John M. MacDougal, Timber Press (2004).

Under the section, Overwintering, it says that in winter, passionflowers suffer from lower temperatures, shorter days, and low light, and therefore this season is the most critical period for these plants. Before night temperatures drop below 10 degrees C, the more sensitive container plants, such as Passiflora quadrangularis and P. vitifolia, should be taken indoors. Depending on their resistance to cold, other species will need to be taken to their winter quarters later on; for now, though, these plants should just be cut back and thoroughly scrutinized for pests. Unlike many other decorative plants, passionflowers keep their foliage in winter, with the exception of certain herbaceous species such as P. incarnata, P. lutea, and P. bryonioides. Do you know if your plant is any of those three (so we will know if its loss of leaves is normal and not a sign for alarm)? [This is from p. 49.]

About the brown sticky spots, it is extremely difficult to make a diagnosis or suggest a treatment, sight unseen. If your plant was not supposed to lose its leaves, and the leaf drop is a sign of severe stress, then those spots could be the result of the plant’s health being poor (as in low resistance to disease). The spots could be bacteria, viral, fungal or even from some insect (although I read through the list of these and could not tell what it might be).

Your plant would be a great candidate for the Master Gardeners to whom the public can take their plants for advice and diagnosis of problems. I found a Master Gardeners of Ontario, which you can search for your particular region.

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Laurel leaves yellowing and dropping

I am losing leaves on my improved English laurel. They turn bright yellow and fall off. I have heard that some loss is normal, but I have one bush losing at least 15 leaves. They have been in the ground now for 4 weeks.

Second question if I could? When a plant turns yellow from the bottom but the top looks normal and wants to bloom what is the problem. Too much water, etc. It just a small flowering plant and the bottom is getting yellow like it is not happy but the top wants to grow fine.

I will take your second question first: When the oldest leaves turn yellow, but the top of the plant still looks fine, that is usually a symptom of nitrogen deficiency. When nitrogen is deficient in the soil, plants will move nitrogen from the oldest leaves to new leaves, resulting in yellowing, or chlorosis, of the oldest leaves. The Sunset Western Garden Problem Solver recommends using a fertilizer containing nitrogen according to directions on the label for the kind of plant you have. You did not mention what kind of plant it is. The fertilizer will give the plant a quick boost. For longer term health, blood meal or fish meal scratched lightly into soil surface around the plant (follow package directions for amount), topped with a one-inch layer of compost will improve the nitrogen content and overall quality of the soil.

(Adding an inch of compost to planting beds in early spring is a good annual practice for replenishing soil nutrients and keeping plants happy.)

You wondered if too much water could be the problem. Overwatering can produce nitrogen deficiencies in the soil by leaching nitrogen down through the soil and away from plant roots. Different plants have different water requirements. Do you know what kind of plant it is? Without knowing what kind of plant it is, and without seeing it, we can only give possible explanations.

Now back to your first question. There are lots of different patterns of yellowing of leaves and each has a different cause. Is it just the bottom, oldest leaves, or newest leaves, or all leaves, or just the edges of leaves, or just between the veins. I would need to know more before even hazarding a guess. But to get an accurate diagnosis for the problems both of your plants are suffering, we recommend you take samples of each, of good leaves and bad and a little bit of soil from around the root zone of each plant to your local Master Gardener Clinic.

You can find a Master Gardener Clinic on the King County Master Gardener website.

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a case of the slime flux

I have a client whose Clematis I just renovated. The client called to say the ends of the cut stems were frothing! What could be causing this?

My best guess (and it is only a guess, since I am basing it solely on your description) is that it could be slime flux. According to the Royal Horticultural Society, “pruned stems may fail to reshoot and ooze a sticky substance–this is known as slime flux.” To confirm this theory, ask the client if the frothy ooze was pinkish orange in hue, and if it had an unpleasant odor. Here is more about this problem from the Daily Telegraph’s garden advice column by Helen Yemm excerpted below:
“This is not so much a disease as a condition that affects some trees and shrubs in spring. Bacteria enter the plant through cracks in the stem – which may well be caused by a combination of adverse weather conditions – and then attack the sap as the plant springs into action early in the year.

Slime flux is often fatal but it depends where the damage is. Everything above the oozing wound will certainly die and should be cut down. However, the plant may well shoot out from below and recover.

Slime flux will not spread to other plants as diseases do, nor will it contaminate the soil like clematis wilt. However, its occurrence would indicate that, for some reason, the general growing conditions in that part of the garden have become unsuitable. If you do lose your clematis, then perhaps it would be a better idea to plant a new one in a less exposed spot.”

browning of leaves in oakleaf Hydrangea

Why are the leaves of my oakleaf Hydrangea turning brown around the edges and falling off?

We do not diagnose plant problems, especially without a sample. It might be wise to bring a sample to your local Master Gardener clinic. You can locate a Master Gardener Clinic within Washington State here.

However, based on my personal experience with my own oakleaf Hydrangea (Hydrangea quercifolia), it is a semi-deciduous shrub that will hold on to its leaves through winter, only to replace them with fresh growth in the spring. All my Hydrangea’s old leaves have turned reddish-brown and look very ratty. Once new growth resumes in spring, I cut off most of the tattered leaves. (Don’t do it too early, in case there is a late frost.)

If you have new growth, do not worry about your shrub, but if you do not have new growth or it is the new growth that is turning brown then you should take a sample leaf into one of the Master Gardener clinics (linked above).

diseases that affect Cyclamens

I am a collector of Cyclamens and grow most of my collection in pots. I believe my C. purpurascens are infected with Botrytis, though I have not had this confirmed by any tests. Last year was particularly bad and I had to remove nearly every leaf from both my plants. This summer, as the new leaves emerged, I sprayed the leaves and surface of the grit with a sulfur solution, which seemed to dramatically reduce the infection rate. Now, the infection seems to be back. Can you suggest some methods of control? Do I have to have it confirmed first? I repotted them early this summer, and sterilized the pots and replaced the grit at that time. What else can I do?

What you have done to control Botrytis is what is recommended by the Pacific Northwest Plant Disease Management Handbook. It does indicate the Botrytis can be seed-borne and grow systemically in the plant. Your real solution may be to obtain plants that are certified disease free.

However in researching Botrytis online, I found an article, “Botrytis Blight of Flowering Potted Plants” in Plant Health Progress, from Plant Management Network International. This article was written by a researcher at Cornell University who suggested that Cyclamen are also susceptible to Fusarium wilt and that the symptoms are quite similar. Therefore, I do think it would be wise to take a sample of your diseased plants to a Master Gardener clinic for confirmation. The Master Gardener clinics in Thurston County can be found at their website.

diseases that affect rhododendrons

My rhododendrons have a problem. What appears to be a white powder covers the buds and spreads up the leaves. What is it, and what can I do to stop it?

I cannot be absolutely certain without seeing the plants, but it sounds as if your rhododendrons could have powdery mildew.

Here is an article from the Washington State University Cooperative Extension which describes this disease. One preventive measure you should certainly take is to clean up all the fallen leaves and twigs under your rhododendrons, because the fungus which causes powdery mildew can overwinter there.

You could bring in a sample to a Master Gardener Clinic, and ask if they can diagnose the disease as well (they are at the Center for Urban Horticulture and other locations–see their website.

common maple problems

I have an uncommon maple (Acer ukuruduense) that I planted two years ago, and which one year ago started sending out long stems from the base, so that now it has a vase shape. One month ago the main (original) stem turned black almost to the ground (the bottom two feet or so are still green), and all its leaves turned brown and fell off. Some of the buds still seem viable, but it seems to be dying at the tips. The rest of the plant is so far showing no signs of trouble. I have not been able to figure out what is going on.

Questions:

1. What is causing this?

2. What, if anything, did I do wrong, and what can I do differently?

3. Might this problem spread to other trees: I have several other small maples in the vicinity.

Other information: The tree is so far just surrounded by bare dirt. This year I watered it frequently with a soaker hose throughout the summer, but last year I was not watering it regularly. It is in full sun, which it is supposed to like.

 

 

 

on diseases that affect junipers

My Sky Rocket junipers are declining. To me it looks like mite damage accompanied by winter damage. The top of the plant is still healthy looking. There are spider mites present. It does not resemble phomopsis, but could be phytophthora. Please let me know what you think.

I checked Diseases of Trees & Shrubs by Sinclair, Lyon and Johnson and Juniper virginiana does not get phytophthora (or at lease this good authority does not list that disease.) It does list a number of other diseases including blight, canker, phomopsis, among many others.

The HortSense website of WSU Cooperative Extension mentions Juniper webworm, which creates heavy webbing, which could resemble mite webbing.

Of course it could be winter damage, like you guess or nitrogen deficiency if the Ph is high (near a lot of concrete?), or salt damage (from melting ice in past winters?).

You should take a sample in to a Master Gardener clinic. If they do not know the cause, you can ask that they “submit it to the diagnostic center at the Center for Urban Horticulture.”

Locate a Master Gardener Clinic within King County at this website.

Japanese Maples and Verticillium wilt

I want to test the roots of our Japanese Maple for Verticillium wilt. Are there places which could test for that?

 

There is information about Verticillium wilt and how to manage it on the Washington State University Extension’s HortSense website.

To have a sample from your Japanese maple diagnosed, you can take samples to a free Master Gardener Clinic, or you can send samples (for a fee) to
WSU Puyallup Research and Extension Center:

go to “How to Submit a Sample,” scroll down to “Plant Problem Diagnosis,” then you can download a form by clicking on “Form C1006.”

My personal experience with this disease is that the Japanese maple lived with it for quite a few years before totally succumbing, at which point we had it removed by an arborist. If you need to remove the tree, you may want to consult this list of plants that are susceptible and resistant to Verticillium.

diseases affecting fir trees

Can I attempt to diagnose a diseased tree online? We’re getting more brown spots on our grand fir and I would like to try to figure out what is wrong.

 

You can attempt it, but you will not know for certain based solely on a comparison of symptoms. You can certainly get an idea of what the potential problems could be. Try the Pacific Northwest Plant Disease Management Handbook online—it has excellent photos. Search for fir.

There are several possibilities with brown spots as symptoms, especially:
*needle casts (there are 3 kinds)
*rust
*web blight
*current season needle necrosis
*shoot blight
*Grovesillea canker
*interior needle blight

The best way to diagnose a problem is to bring photos of the affected tree along with samples (if you can reach them) to your local county extension agent or Master Gardener diagnostic clinic.