Diseases of California native plants

Questions about diseases of California Native Plants

My ceanothus has been in place growing beautifully for 15 years. I live in Clairemont Mesa, (92117) with clay/sand/cobble 'soil' over hardpan. Hardpan varies from 4" to 18" below the surface. The only real soil derives from 15 years of bark mulch. Drainage is a joke! I overhead irrigate with my old oscillating sprinkler about once every two weeks in the summer or when the soil becomes dry. I do not use fertilizer at all. Over this last winter, the ceonothus turned brown and developed woody warts about 1" wide on the larger stems and branches. It is now completely dead and I have chopped it down. I have several other natives and even a few Mediterraneans that are suddenly turning brown and dying. Any idea what this might be and how I can remedy it?

I figured there was some root rot going on, but those 1" wooden warts on the stems are pretty scary looking!

they drowned last winter and died as summer showed up.
the roots basically died of root rot in the heavy wet soil, roots died off and were not there, in their place pathogens were attacking plant, plant could not regenerate new roots fast enough to pull enough moisture and defend from pathogens.
There is not much you could have done.
we've had the problem here when we get a two inch thundershower in August, they die very fast
also get it when a new caretaker of a native garden waters the planting for 24 hours in July...

you got fifteen good years out of them
the swellings are odema

I bought a whole bunch of Sugarbushes and some Manzanitas and Sages and a couple of small oaks from you guys last years. They got all that winter rain
and all seem to be growing well.
I have a Coast Live Oak,I suspect it may be a Scrub Oak, that I planted as a fifteen gallon about ten years ago. It is about twenty feet tall and about
twenty feet across. It is growing within about fifteen feet of my leach lines/septic field. I have not watered it at all since last year.
This tree seems to have a considerable amount of powdery mildew on all the new growth, which now dies back and turns brown, all the green leaves seem
to have rough brown patches underneath and brown spots on top. I think the major problem is the mildew.
Does anybody know the best way to deal with this?
Will it "grow out?"

ignore it

Will it "grow out?"

almost every time, they do not grow in Northern Oregon, too much rain, as it goes back to normal rainfall it should settle down

The three mama bear manzanitas that I ordered from you and received were light green in color and had purplish spots on the lower leaves. You had told me that it is nothing to worry about, they are just pushing new growth. However, I don't see any new growth yet, just the leaves with the purple spots turning brown and crispy and falling off. I have not been overwatering.

What is happening? Are they dying?

If the spots are on the older leaves it is probably leaf spots from the cool/wet weather we have had this winter and spring. This is normal and occurs in nature. Our plants are grown in the open, for the most part, so that they will be hardy as possible when they go to the customers gardens. We do not use insecticides, or fungicides, bactericides, etc. on the plants so there will be some leaf spots, etc. Leaf spots are caused by several organisms, mostly bacteria, and fungi, that occur and spread during periods of wet/warm or wet/cool weather. Usually, the leaf spots are minor, and we do not worry about them as we have had no major problems in 30 years. They usually also occur more often on the lower leaves as the water that hits the soil in the pots splashes up more often on those leaves, and the moisture level is also higher at that lower level where the pot is surrounding the area where the lower stem emerges from the soil. If the spots coalesce, then a few of the lower/older leaves may fall off. This should not be a problem.
As a rule, after planting, manzanitas just "sit there" in the garden for about one year, growing their roots. The second year the tops start growing.
Just follow the planting guide carefully and you should not have any problems. No, I do not think they are dying.

I purchases several varies of manzanita from you last year, they seem to be doing fine except for the Dr. hurd's which are losing leaves from ? the get spots , look black , on lower leaves and then sots turn leaf gray and then the dry up and die. Is they anything I can do? thank you

you're describing drowning

Can you please give me some advice on what to do with a small
(35 inch)coastal live oak that has a few branches of witches broom.
Otherwise it is a healthy looking tree. We planted it in the fall of last
year. We live in Cambria and there are other live oaks around us. Everyone
once in a while I see one with witches broom.

Thank you for your quick reply! It is possible the oak doesn't get good air
flow. I will cut back some plants around it.
We also purchased some plants from Las Politas in the late fall of 2002.
They were all very small. The arctostaphylos 'Sunset" are doing very well
and have lots of new growth. The rhamnus 'Mound San Bruno" haven't done
anything. They are just sitting there looking the same. Are they slow to get
started? Should we be doing something with them. I only water them if they
are dry. You were not there the day we purchased them. Some neighbors have
the 'Mound San Bruno" and they are growing very nicely after about 3 years.

It is commonly caused by a fungus, sometimes bacteria, sometimes
microplasma usually because the plant grew too fast.
Too much shade, poor air flow, too much fertility, drip irrigation, too
much water all can cause it.
They can grow out of it, but it is usually best to cut the infected part
off, garbage bag it and send off to dump.
The remaining tree should grow back fine, if you find the variable that's
off.

I have been to your nursery and now seeking expert advise.

My iris douglasiana have rust and thrips. What to do?
Any organic oil or spray suggestions? Which problem do I tackle first? If I cut them to the ground...how long will it take for the foliage to grow back?

Second problem....I planted ribes viburnifolium on a slope three years ago. Never fertilized. Now they look horrible. What organic foliage fertilizer do you recommend.

Last, it there a bagged mulch sold at Home Depot that you recommend for natives? I need to find a recommended "bagged" mulch because the property in need of mulch is on a steep hill and loose mulch delivered by truck is too difficult to move around the hillside.

Thanks for you feedback. Need to make a trip to your nursery this fall to do a serious planting.

I live in Laguna Beach right on the coast.....the iris are planted in a ravine behind the house in full sun. They are watered twice a week by sprinkler system. The iris have not been mulched or fertilized. (I thought fertilizing natives was taboo). Second....the ribes have been planted in 1/2 sun and 1/2 shade. They were mulched with redwood bark about a year ago. Thanks for the feedback again.... So let me get this straight ...Iris...water is good, no mulch. Do I cut them back or spray oil for the thrips??? What kind of fertilizer? The tips also look burned. Is that normal??? Do I cultivate around them and loosen soil?? Dig up and divide? I planted about 300 iris 3 years ago, so I am trying to make a large investment in time and money look better. Ribes....mulch again...what kind? Cut back?? What's the best way to fertilize??? Grow Power??? How about a foliage spray?? I think they need a boost of nutrients of some kind but since I live at the beach, I am trying to be careful about what I use. Thanks for your advise.

what town, soils how are you watering, how much shade, were they mulched or fertilized? the iris never have this problem unless something is way off, sprays will not fix them except short term, I'm looking for the possible problems, Iris do not usually get rust and thrips unless something is off. Iris will tolerate a lot of water, but do not like much mulch. Is the soil dry inspite of the sprinklers? They also tolerate really rich clay soils, is the soil sandy or gravel? The full sun is fine, they get scale and other problems in shade. how much sun are the Ribes getting? I really think these guys are getting too much sun, one hour of day sun it too much, they need shade unless it is really cool. Like and see if there is a pattern following the sun to the uckky.

I couldn't be happier with the help I received at your Escondido location. I'm new to California, and having read about water shortage and being sensitive to the impact of urban population on the environment, I vowed to do my part in creating a water conserving and "natural" yard. Morgan was absolutely phenomenal in helping me to plan my little front yard so that it would fit my requirements, both environmentally and esthetically. I made my meager purchases and stripped and relandscaped my yard. The half-dead, but persistent bermuda grass (I turned off the irrigation immediately after moving in) was removed with a total of 3 inches of grass+topsoil. This was replaced with unamended decomposed granite. We dug, danced (plant dance), and watered copiously. The manzanita, ceanothus, zauschneria, penstemons, and artemisia are all flourishing (well, two seem not to be responding quickly, but they look stepped on). In any case, it sounds like there is nothing i can do right now except wring my hands and fret over my little Salvia. Maybe little aphid-sized scarecrows... After all that, here is my question. My Bees Bliss has been turned into an aphid farm by my ever-present ants. The curling new leaves hide them like sheltered sheep. I have rinsed, removed by hand, then sprayed with a weak dish soap solution. Please let that not have been a stupid move! I read your help about the return of the natural predators in the spring (it's February, just in case you don't answer email for a while). The plant is growing, but about 15% of the new growth succumbed to those little leaf-suckers. Is there anything else I should do? By ladybug larvae? Chant? Blow incense at the leaves? Your expert opinion is appreciated. By the way, we have a house on a canyon, and as the budget allows, hope to do some planting on our property there. We're charter members of the newly formed Friends of Azalea Park Canyon Committee and distribute your Web site whenever possible. P.S. Morgan is a real gem--excellent customer service, knowledgeable and professional presentation, and just a nice person to do business with. Hi and thanks for the reply! Hmmm, overwatering you say? I read your lecture on watering plus the handout. Something about it not being possible to overwater when you first plant. 30 gallons per plant depending on how dry it is. We did that pretty carefully. Then check the soil for dryness below the surface a nd water about every two weeks, give or take, depending upon whether the soil is dry. Now we have had some actual rain lately, so I haven't had to water. The whole thing has been planted only about a month. So I'm not sure how we could have overwatered. I put the sprinkler out there one other time after the initial planting. There's no irrigation there. I used the "drink a beer" timer (well, a glass of wine, but maybe that's more water!) In any case, it sounds like there is nothing i can do right now except wring my hands and fret over my little Salvia. Maybe little aphid-sized scarecrows... Best of business to you and thanks for a great site. 1. Good for Morgan! 2. I'll send some photos (low-res) I'm photographing every two weeks. Okay, I'm a little over-obsessed about this, but I LOVE my new yard, and I want comparison pics for when my plants fill out their assigned spots. Again, hmmmmm. Zero fertilizer! Decomposed granite only. No additives. South facing, raised yard. No obstructions to sunlight except at sunrise (neighbor's garage to the east) From 8:30 AM on (now in Feb.) there is direct sun. There may be some shade from porch overhang late in the afternoon. I'll check. Watered when planting and about 2 weeks later. But then we had that "heavy" (for CA) rain. No drip, no built-in sprinklers. I have to manually water. I could have watered too long on the two-week water. I set the sprinkler on that side on very low output for an hour or two. Then it rained. Nothing before or since. I hand water the "foreign" salvias that are in pots nearby. I use a watering can, and those are sparsely watered. The one Salvia Bee's Bliss is the only thing with any aphids. We have tons of ants around our house and there were incredible numbers of aphids on a hibiscus last fall that the previous owners left behind. But that's nowhere near this Salvia, and that plant is clean now (it's going to be removed and given away soon when I replant the side yard, which has nothing to do with anything.) All other plants look happy and bug free. I was happy to note a ladybug near the area of the Salvia and am hoping it is bringing all its relatives. After a little soap spray last week, I'm seeing very few aphids on that Salvia and no ant farmers. I'm hoping that they'll take their flock elsewhere. I'll try the wait and see approach. And no more water! There is redwood bark over the yard (with margins around the plants. So I'm thinking that the soil is holding the water content. So I'll widen the bark- free margins around the plant bases to increase evaporation. I'd prefer no bark, but the neighborhood cats wiped out last year's plantings in another area that they thought was a litter box. So I have large river rock and bark now. More than you wanted to know? Photos are attached. I'm trying to figure out what's what down there in the canyon. Joined the Friends of ... Park Canyon Committee--we're now founding members-- and did a canyon walk through. Lots of morning glory and castor bean arrondo donax that folks have been trying to get rid of for a while. I was plucking samples of other plants to see if I could get them identified somewhere. We need to figure out what belongs and what doesn't. My yard actually extends back into the canyon, and I'd like to plant some stock from Las Pilitas back there once I figure out what will work. I'm on the north facing slope, and it's quite steep. In the mean time, I'll find a better location for the sage and see what will work in its old spot. No water most of the year, but it gets the winter/spring rain run-off from the roof probably. Thanks for the evaluation and other info.

it really sounds like overwatering(almost any is overwatering) yeah she just got two pay raises and health... > now if we could just find two more we could afford > Thanks(and turn off the water) > If that's not it, email more info, and pictures(small) it doesn't look like you have rain gutters > move the Salvia, it's drowning > whcih way is that wall facing? after all of this, she sent a few pictures, there were two little leaves wilted, probably from being stared out. About 1-2% of plant wilted, 98% fine. These are wild plants, not plastic ones. But her plants still looked better than plastic ones. I know some of you have replaced the small dressed up dog with the 2 foot by 20 foot front yard, but relax, it ain't a biggy if one plant losses one leaf it is not a big deal.

My ceanothus has been in place growing beautifully for 15 years. I live in Clairemont Mesa, (92117) with clay/sand/cobble 'soil' over hardpan. Hardpan varies from 4" to 18" below the surface. The only real soil derives from 15 years of bark mulch. Drainage is a joke! I overhead irrigate with my old oscillating sprinkler about once every two weeks in the summer or when the soil becomes dry. I do not use fertilizer at all. Over this last winter, the ceonothus turned brown and developed woody warts about 1" wide on the larger stems and branches. It is now completely dead and I have chopped it down. I have several other natives and even a few Mediterraneans that are suddenly turning brown and dying. Any idea what this might be and how I can remedy it? I figured there was some root rot going on, but those 1" wooden warts on the stems are pretty scary looking!	they drowned last winter and died as summer showed up. the roots basically died of root rot in the heavy wet soil, roots died off and were not there, in their place pathogens were attacking plant, plant could not regenerate new roots fast enough to pull enough moisture and defend from pathogens. There is not much you could have done. we've had the problem here when we get a two inch thundershower in August, they die very fast also get it when a new caretaker of a native garden waters the planting for 24 hours in July... you got fifteen good years out of them the swellings are odema
I bought a whole bunch of Sugarbushes and some Manzanitas and Sages and a couple of small oaks from you guys last years. They got all that winter rain and all seem to be growing well. I have a Coast Live Oak,I suspect it may be a Scrub Oak, that I planted as a fifteen gallon about ten years ago. It is about twenty feet tall and about twenty feet across. It is growing within about fifteen feet of my leach lines/septic field. I have not watered it at all since last year. This tree seems to have a considerable amount of powdery mildew on all the new growth, which now dies back and turns brown, all the green leaves seem to have rough brown patches underneath and brown spots on top. I think the major problem is the mildew. Does anybody know the best way to deal with this? Will it "grow out?"	ignore it Will it "grow out?" almost every time, they do not grow in Northern Oregon, too much rain, as it goes back to normal rainfall it should settle down
The three mama bear manzanitas that I ordered from you and received were light green in color and had purplish spots on the lower leaves. You had told me that it is nothing to worry about, they are just pushing new growth. However, I don't see any new growth yet, just the leaves with the purple spots turning brown and crispy and falling off. I have not been overwatering. What is happening? Are they dying?	If the spots are on the older leaves it is probably leaf spots from the cool/wet weather we have had this winter and spring. This is normal and occurs in nature. Our plants are grown in the open, for the most part, so that they will be hardy as possible when they go to the customers gardens. We do not use insecticides, or fungicides, bactericides, etc. on the plants so there will be some leaf spots, etc. Leaf spots are caused by several organisms, mostly bacteria, and fungi, that occur and spread during periods of wet/warm or wet/cool weather. Usually, the leaf spots are minor, and we do not worry about them as we have had no major problems in 30 years. They usually also occur more often on the lower leaves as the water that hits the soil in the pots splashes up more often on those leaves, and the moisture level is also higher at that lower level where the pot is surrounding the area where the lower stem emerges from the soil. If the spots coalesce, then a few of the lower/older leaves may fall off. This should not be a problem. As a rule, after planting, manzanitas just "sit there" in the garden for about one year, growing their roots. The second year the tops start growing. Just follow the planting guide carefully and you should not have any problems. No, I do not think they are dying.
I purchases several varies of manzanita from you last year, they seem to be doing fine except for the Dr. hurd's which are losing leaves from ? the get spots , look black , on lower leaves and then sots turn leaf gray and then the dry up and die. Is they anything I can do? thank you	you're describing drowning
`Can you please give me some advice on what to do with a small` `(35 inch)coastal live oak that has a few branches of witches broom.` `Otherwise it is a healthy looking tree. We planted it in the fall of last` `year. We live in Cambria and there are other live oaks around us. Everyone` `once in a while I see one with witches broom.` `Thank you for your quick reply! It is possible the oak doesn't get good air` `flow. I will cut back some plants around it.` `We also purchased some plants from Las Politas in the late fall of 2002.` `They were all very small. The arctostaphylos 'Sunset" are doing very well` `and have lots of new growth. The rhamnus 'Mound San Bruno" haven't done` `anything. They are just sitting there looking the same. Are they slow to get` `started? Should we be doing something with them. I only water them if they` `are dry. You were not there the day we purchased them. Some neighbors have` `the 'Mound San Bruno" and they are growing very nicely after about 3 years.`	`It is commonly caused by a fungus, sometimes bacteria, sometimes` `microplasma usually because the plant grew too fast.` `Too much shade, poor air flow, too much fertility, drip irrigation, too` `much water all can cause it.` `They can grow out of it, but it is usually best to cut the infected part` `off, garbage bag it and send off to dump.` `The remaining tree should grow back fine, if you find the variable that's` `off.`
I have been to your nursery and now seeking expert advise. My iris douglasiana have rust and thrips. What to do? Any organic oil or spray suggestions? Which problem do I tackle first? If I cut them to the ground...how long will it take for the foliage to grow back? Second problem....I planted ribes viburnifolium on a slope three years ago. Never fertilized. Now they look horrible. What organic foliage fertilizer do you recommend. Last, it there a bagged mulch sold at Home Depot that you recommend for natives? I need to find a recommended "bagged" mulch because the property in need of mulch is on a steep hill and loose mulch delivered by truck is too difficult to move around the hillside. Thanks for you feedback. Need to make a trip to your nursery this fall to do a serious planting. I live in Laguna Beach right on the coast.....the iris are planted in a ravine behind the house in full sun. They are watered twice a week by sprinkler system. The iris have not been mulched or fertilized. (I thought fertilizing natives was taboo). Second....the ribes have been planted in 1/2 sun and 1/2 shade. They were mulched with redwood bark about a year ago. Thanks for the feedback again.... So let me get this straight ...Iris...water is good, no mulch. Do I cut them back or spray oil for the thrips??? What kind of fertilizer? The tips also look burned. Is that normal??? Do I cultivate around them and loosen soil?? Dig up and divide? I planted about 300 iris 3 years ago, so I am trying to make a large investment in time and money look better. Ribes....mulch again...what kind? Cut back?? What's the best way to fertilize??? Grow Power??? How about a foliage spray?? I think they need a boost of nutrients of some kind but since I live at the beach, I am trying to be careful about what I use. Thanks for your advise.	what town, soils how are you watering, how much shade, were they mulched or fertilized? the iris never have this problem unless something is way off, sprays will not fix them except short term, I'm looking for the possible problems, Iris do not usually get rust and thrips unless something is off. Iris will tolerate a lot of water, but do not like much mulch. Is the soil dry inspite of the sprinklers? They also tolerate really rich clay soils, is the soil sandy or gravel? The full sun is fine, they get scale and other problems in shade. how much sun are the Ribes getting? I really think these guys are getting too much sun, one hour of day sun it too much, they need shade unless it is really cool. Like and see if there is a pattern following the sun to the uckky.
I couldn't be happier with the help I received at your Escondido location. I'm new to California, and having read about water shortage and being sensitive to the impact of urban population on the environment, I vowed to do my part in creating a water conserving and "natural" yard. Morgan was absolutely phenomenal in helping me to plan my little front yard so that it would fit my requirements, both environmentally and esthetically. I made my meager purchases and stripped and relandscaped my yard. The half-dead, but persistent bermuda grass (I turned off the irrigation immediately after moving in) was removed with a total of 3 inches of grass+topsoil. This was replaced with unamended decomposed granite. We dug, danced (plant dance), and watered copiously. The manzanita, ceanothus, zauschneria, penstemons, and artemisia are all flourishing (well, two seem not to be responding quickly, but they look stepped on). In any case, it sounds like there is nothing i can do right now except wring my hands and fret over my little Salvia. Maybe little aphid-sized scarecrows... After all that, here is my question. My Bees Bliss has been turned into an aphid farm by my ever-present ants. The curling new leaves hide them like sheltered sheep. I have rinsed, removed by hand, then sprayed with a weak dish soap solution. Please let that not have been a stupid move! I read your help about the return of the natural predators in the spring (it's February, just in case you don't answer email for a while). The plant is growing, but about 15% of the new growth succumbed to those little leaf-suckers. Is there anything else I should do? By ladybug larvae? Chant? Blow incense at the leaves? Your expert opinion is appreciated. By the way, we have a house on a canyon, and as the budget allows, hope to do some planting on our property there. We're charter members of the newly formed Friends of Azalea Park Canyon Committee and distribute your Web site whenever possible. P.S. Morgan is a real gem--excellent customer service, knowledgeable and professional presentation, and just a nice person to do business with. Hi and thanks for the reply! Hmmm, overwatering you say? I read your lecture on watering plus the handout. Something about it not being possible to overwater when you first plant. 30 gallons per plant depending on how dry it is. We did that pretty carefully. Then check the soil for dryness below the surface a nd water about every two weeks, give or take, depending upon whether the soil is dry. Now we have had some actual rain lately, so I haven't had to water. The whole thing has been planted only about a month. So I'm not sure how we could have overwatered. I put the sprinkler out there one other time after the initial planting. There's no irrigation there. I used the "drink a beer" timer (well, a glass of wine, but maybe that's more water!) In any case, it sounds like there is nothing i can do right now except wring my hands and fret over my little Salvia. Maybe little aphid-sized scarecrows... Best of business to you and thanks for a great site. 1. Good for Morgan! 2. I'll send some photos (low-res) I'm photographing every two weeks. Okay, I'm a little over-obsessed about this, but I LOVE my new yard, and I want comparison pics for when my plants fill out their assigned spots. Again, hmmmmm. Zero fertilizer! Decomposed granite only. No additives. South facing, raised yard. No obstructions to sunlight except at sunrise (neighbor's garage to the east) From 8:30 AM on (now in Feb.) there is direct sun. There may be some shade from porch overhang late in the afternoon. I'll check. Watered when planting and about 2 weeks later. But then we had that "heavy" (for CA) rain. No drip, no built-in sprinklers. I have to manually water. I could have watered too long on the two-week water. I set the sprinkler on that side on very low output for an hour or two. Then it rained. Nothing before or since. I hand water the "foreign" salvias that are in pots nearby. I use a watering can, and those are sparsely watered. The one Salvia Bee's Bliss is the only thing with any aphids. We have tons of ants around our house and there were incredible numbers of aphids on a hibiscus last fall that the previous owners left behind. But that's nowhere near this Salvia, and that plant is clean now (it's going to be removed and given away soon when I replant the side yard, which has nothing to do with anything.) All other plants look happy and bug free. I was happy to note a ladybug near the area of the Salvia and am hoping it is bringing all its relatives. After a little soap spray last week, I'm seeing very few aphids on that Salvia and no ant farmers. I'm hoping that they'll take their flock elsewhere. I'll try the wait and see approach. And no more water! There is redwood bark over the yard (with margins around the plants. So I'm thinking that the soil is holding the water content. So I'll widen the bark- free margins around the plant bases to increase evaporation. I'd prefer no bark, but the neighborhood cats wiped out last year's plantings in another area that they thought was a litter box. So I have large river rock and bark now. More than you wanted to know? Photos are attached. I'm trying to figure out what's what down there in the canyon. Joined the Friends of ... Park Canyon Committee--we're now founding members-- and did a canyon walk through. Lots of morning glory and castor bean arrondo donax that folks have been trying to get rid of for a while. I was plucking samples of other plants to see if I could get them identified somewhere. We need to figure out what belongs and what doesn't. My yard actually extends back into the canyon, and I'd like to plant some stock from Las Pilitas back there once I figure out what will work. I'm on the north facing slope, and it's quite steep. In the mean time, I'll find a better location for the sage and see what will work in its old spot. No water most of the year, but it gets the winter/spring rain run-off from the roof probably. Thanks for the evaluation and other info.	it really sounds like overwatering(almost any is overwatering) yeah she just got two pay raises and health... > now if we could just find two more we could afford > Thanks(and turn off the water) > If that's not it, email more info, and pictures(small) it doesn't look like you have rain gutters > move the Salvia, it's drowning > whcih way is that wall facing? after all of this, she sent a few pictures, there were two little leaves wilted, probably from being stared out. About 1-2% of plant wilted, 98% fine. These are wild plants, not plastic ones. But her plants still looked better than plastic ones. I know some of you have replaced the small dressed up dog with the 2 foot by 20 foot front yard, but relax, it ain't a biggy if one plant losses one leaf it is not a big deal.