Some of our clematis armandii leaves have gone like this. Is this an important problem, or is this just something that happens at this time of year? John
Hi John: It may be better that someone located closer to you tries to help but I know what I would suspect if this plant were grown here. Give me some background on your soil and its type, what fertilizers or soil amendments you use and the last time you fertilized this plant. How widespread throughout the plant is the discoloration on the leaves? Were the black discolored areas in the leaves first seen before the burned tips and the other deadened areas were evident? Were the leaves exposed to long periods of hot, direct sunlight and were the leaves wet when they were exposed to the sunlight? How old is the plant and how long has it been planted in the ground or is it grown in a container? Are the leaves some of the older leaves on the plant? Just me being curious, what variety is this Clematis such as Snowdrift, Apple Blossom or Hendersonii Rubra? What I see does not appear to be your worst fear and that is Clematis Wilt. Do you have any Camellias or in the last few years newly brought in Rhododendrons or Azaleas growing near this Clematis? What do the underside of the leaves look like? What I would like to know if there are any soft tissue ruptures on the underside of the leaves also. < Is this an important problem, or is this just something that happens at this time of year? > Just to ease your mind a little, a multi-nutrient deficiency can cause the cellular tissue ruptures that I am seeing. It is quite common with Sasanqua Camellias when our soil mediums have had most of the nutrients depleted or have been leached out. The speckling on the leaves for Camellias and the evergreen Clematis is also an indication that there is not enough Oxygen movement in the soil. Important problem, could be but I am not going there yet. Yes, this condition is common with the evergreen Clematis we've grown here. For us, it was the older leaves on the plant that would do this to us. Jim
common problem John, Jim and all--this is a common but still somewhat mysterious complaint with armandii here in the Vancouver, BC area. I have over 100 in 1 gal. containers, many of which are suffering varying amounts of leaf browning. Many of those in the most sun exposed areas are looking the best, so trying to figure out a cause is difficult for me. I do assume that this is a type of wilting where the plant is unable or unwilling to supply enough water to the extreme leaf tips and sometimes entire shoots, which wind up browning off and dying. I depotted one of my worst examples, and did find the plant very potbound. This probably doesn't directly answer John's question, since his is most likely planted out in the ground. Still, there could be some water shortage after our hot, dry summer, esp. up under the eaves of a house. Also any fertilizing could cause, or worsen, the situation. I don't know when I'm going to learn my lesson that too little fertilizer is much better than too much...in this case i did give the armandii's a good dose of liquid fish before the leaf browning showed up here. Similar "scorch" on some 2 gal. rhodos nearby is more like "sunburn", but would have been related to the high salt content of the fish combined with the hot sunny spells with low humidity that we enjoyed but most of our broadleaved evergreens did not. That all said, I continue to be mystified by many massive armandii's growing in peoples yards here with no sign of a problem, while others struggle and show considerable dieback/leaf browning. Wish I knew a few more tricks with this plant! Glen
Hi Glen: Just a few quick comments: Bear in mind that what happens to us here may not occur elsewhere. There is a great deal of variance in how plants behave in Canada and the Pacific Northwest as opposed to the drier and warmer areas of California. What we perceive as an issue here may be thought of as being normal or naturally occurring in another area until something shows up to cause concern in those other areas. The ruptures I am seeing on the leaves of John's plant is usually attributed to Calcium deficiency on Clematis Armandii. When I refer to fertilizers or fertilizing I am not always referring to applications of Nitrogen. We found that low Nitrogen levels worked best for us. Yes, high salt content can cause the tips to burn, so can an overload of Magnesium. Nitrogen burning acts a little differently on Armandii than what we are seeing from John's plant. Armandii grown in the ground as opposed to them growing in containers can be a marked difference in how the plants behave. Grown in a saran house in 50% shade with overhead sprinklers we would see tip burning if the leaves were wet and then exposed to hot, direct sun or hot winds. Margin burning is not nearly as common as tip burning for us with out heat and low humidity here. Splotch burning tells me something else such as Calcium and Manganese deficiency as well as possible Magnesium toxicity which can come about as a result of certain fish emulsions applied to saline and alkaline soils. What I am more interested in knowing is the soil, its type and how compacted it may be. I know that it may seem hard for people to understand but we do get compaction of another sort with plants grown in containers in that what we see of the soil appears okay and the water holding capacity seems good but there is no air movement in the roots from the soil particles coalescing to the point that we have a compacted soil without an actual compaction. Compaction generally refers to a layer of soil that becomes hardened in which water cannot penetrate through it very easily. That is essentially what our hard pan layer is like here and our layers may be 1-2 feet thick. I've even witnessed land dynamited just to break the hard pan layer as a D9 with a 5 foot, 3-prong ripper shanks could not break the compacted clay pan layer. Even with container grown plants we may experience soil that holds water fine but because there is so little air movement in the soil that the soil actually does become compacted in another sense (super saturated) to the point that no air movement is occurring even after the soil becomes dry. Compacted soil to me means little or no Oxygen movement at all. The roots in effect suffocate due to no free Oxygen for them to breathe in. The above happens a lot with container grown Camellias when the soil is starting to break down on us and we've seen it with Clematis Armandii also that have plenty of silt in the potting medium but little organic matter to enable air pockets in the soil. When we repotted the plants and added in lots of humus into our soil mix we no longer experienced the topographical tissue ruptures we were seeing on the cuticle of both the Camellias and the Clematis. The endodermic discoloration is what bothers me in John's plant as that condition will not be immediately cured by adding in lots of organic matter into the soil mix. That is something else. Technically, John's condition is not a Wilt as John's plant would be dead at this point in time. Clematis Wilt acts very fast, one day the plant looks sickly and in a week it is deader than a doornail. I've never seen Clematis Wilt here but I have seen it in wetter and less warm climates than ours and with plants grown more so in acid soils as opposed to saline or alkaline soil conditions. As far as your condition on the one gallons you may want to post some pics of them. I would be more interested to see if the symptoms I am seeing on John’s leaves and the leaves of your Armandii are similar, yet different. Pot bound plants also do not have Oxygen to breathe. What generally happens to pot bound plants that have not rooted in, in some way, into the soil? Serious dieback after advanced stages of leaf browning may be something quite other than what John’s plant is or will be experiencing. Jim One last word: I have seen a form of Phytophthora cause similar, yet different leaf effects to Clematis Armandii, sans the ruptures, that are evident in John’s image on the cuticle. I’ve not seen it here though but I have seen it on Apple Blossom in a Plant Preservationist Conservatory in Northern California and elsewhere in the Pacific Northwest on Deciduous and Kurume Azaleas especially, as well as a host of Rhododendrons. I am no longer at liberty to discuss that pathogen issue in an open forum other than to say that tissue scarring does occur on the soft wood stems with advanced lesions showing up later on the hard wood. Left uncontrolled or untreated the above plants usually perish in two years after initially becoming infected.
potbound problems Jim--I really appreciate your detailed responses backed up by real life experience. As a newbie in this biz, I feel I can only receive and not give much at this point. Your comments regarding calcium vs. magnesium, deficiencies and toxicities are very helpful. I've eliminated almost all use of dolomite and begun using high calcium lime, along with a raw (mined) humate product and a glacial dust that is easily available up here, for the bulk of my mineral supplement/"lime" inputs this year. I did hear of research in Scotland that found rhodos did better with high Mg and low Ca, but that was the only convincing info supporting extra Mg that I've run across. Low nitrogen is also noted, having seen this leaf damage following liquid fish application I will be much more careful. I did seem to find a top dress of bloodmeal on one block of plants did very well, compared to the others done with the fish...just my one season's experience here. I will be looking more carefully for evidence of the "compaction" problem now that I know it is possible in containers...slow growers like the camellia would certainly be more likely as they can be longer than a year in the same size container. I have a few small conifers like that...growing so slow they don't really need repotting unless the breakdown of the bark and compost makes for too dense a mixture...certainly makes sense. A digital camera is more and more desirable, I'm sure you'd have some comments if I could show the tip burn as well as a few short lengths of new growth that have browned/wilted. Phytophthora is unfortunately quite common on rhodo/azaleas and other evergreens here...no discoloration of roots to suspect that on the clematis, so far. Thanks again for your thoughts, Jim. Hopefully some of the other locals have some useful experiences on this... Glen
Hi Glen: A quick follow up. We had evidence of Calcium and Manganese deficiency showing on the leaves when we felt there was ample amounts of both nutrients in the soil. We did a soil test on the soil medium and a plant ash analysis on the leaves. What we learned did not surprise us, as we suspected it. We saw that we did indeed have ample amount of Calcium and Manganese in the soil and yet we were deficient in the leaves. By adding in more organic matter, for us forest humus, it was not long that the tied up, the better term is bound, Calcium and Manganese were then made much more readily available to the plant. The water mold forms of Phytophthora will always be a problem for us in wetter and cooler climates than here. It is a still relatively unknown blast form of Phytophthora is what I will not openly talk about any more. There are too many misconceptions with it and another non-water mold form of Phytophthora to suit me. I'll defer and wait until more people know more about both of them. One form is much more lethal on certain Azaleas and various forms (more so on native species) of Rhododendrons than the other form is however. The Apple Blossom at the Plant Conservatory (I did not name it) got hit in mid to late Summer. I saw it in the early Spring when in bloom and it was its last time for it to bloom as well. What a sight though as I had not ever seen an Evergreen Clematis that large. That one plant was over 100 feet long, pruned at 5' tall and made a lasting impression that no one would soon forget if they ever saw it in bloom. We took photos of it and of the stems and hard wood damage but what a lousy feeling we had for the 5+ hour drive home also. During the Summer they ordered 10 one gallon Apple Blossoms from us to replace it and plant elsewhere and ordered from us, the originating source nursery, 10 one gallon Hendersonii rubras. Jim
Re: common problem Hi Jim, Do you still have armandii at your nursery, if so, I'd like to purchase some, as well as armandii 'Apple Blossom' if you have them. Thanks and Best Regards, -chad
