3 problems: crepe myrtle, oleander, duranta

[jeh]

Hi! I live in a very mild area in So California. Soil is amended clay. They were all planted approx. 1 year ago. I water 1 - 2 times a week depending on weather temps. (Unfortunately, we don't have to worry about rainfall here. ) I've noticed no bugs or any other obvious pests.

The dwarf oleander is 1 of 5. This is the only one that has buds that are turning brown and falling off. The other 4 are fine.

The crepe myrtle's leaves look burned around the edges.

Three of five duranta's just look droopy.

Any help / ideas you may have will be most appreciated!

[applestar]

I'm not familiar with care requirements for these plants, so I'll just ask a general question -- when you say you water 1-2 times a week, how do you water and how much do you water?

Do you check the soil around them to see that the water has soaked in?

[catgrass]

The duranta looks like it needs water-something may be in its roots. The crepe myrtle looks like the start of powdery mildew.

[jeh]

I use a trowel to dig down just a little to see how wet/dry the soil is b4 watering since clay can be deceitful on the surface. If wet, no water. If damp, some water. If really dry, I'll give a good hose watering and go back 5 minutes later and water again. Fortunately, the clay isn't so bad that it pools. It does seem to drain, not sure how fast. But I wouldn't say that our soil is 'well draining'.

[jeh]

I agree, the duranta does look rather parched. I have 5 of them planted in a row, and the funny thing is that numbers 1 and 4 look fine with the others looking droopy despite how much water I give them. I'm so confused.

[ElizabethB]

Hi Jeh - Wow - what a mess. All three of your plants are very hardy especially in SoCal where you do not have issues with humidity like I do in south Louisiana.

Not all pest are conspicuous. Use a magnifying glass and inspect the leaves top and bottom, leaf joints and inside the oleander flowers.

The lighting on the crepe myrtle is not the best. Is there a dusty looking film on the leaves that rubs off?

The Mods do not like for me to make this recommendation but in this case I think it is justified. Take leaf, stem and flower samples from all of the plants. Put them in a labeled zip lock.

Take a soil sample from each plant. Use a sharp spade and cut a slice of soil the depth of the spade head ad an inch wide. Crumble the soil and collect 1/2 cup in a labeled zip lock.

Bring your plant and soil samples to your County Extension Office. Have soil test done. Well worth the few $'s. I do not think there is a charge to have the plant material examined.

Caution: not all states have a responsive Extension Office system. CA is a state with a bad reputation. Be prepared to wait for your test results.

My next focus would be on watering. The Duranta really looks like it is suffering from either over or under watering. Clay can be the culprit of both. It can cause water to pool and drown your plants or it can cause water to run off too quickly.

You said that you amended the clay. How and with what?

Clay is a real B to deal with. It can take years of amending to make it suitable for planting.

Would you trust a Physician who prescribed medication without a diagnosis? Apply that to your soil. You really need a diagnosis of the soil condition.

Good luck.

I am interested in knowing what the results of your test are.

[jeh]

Why thank you, Your Majesty. That's a lot of good info. And you're soooo right about dealing with clay. It is truly a B.

When digging a hole, I go a little bigger than is usually recommended. That's so I can give the plant a little more room of amended soil. I generally use an amendment that my nursery suggests, can't remember the name of it, or Amend. I mix it 1/2 & 1/2 with the dug up soil and then plant as usual.

I just took a magnifying glass outside and looked closely but didn't notice anything on any of the plants. Good or bad? I don't know.

I'm assuming you're looking for powdery mildew on the crepe myrtle since I've had trouble with that on others that I've had in the past. Since it was only planted last year, it's still small enough that I was able to give it a good going over. No powder, just the edges of the leaves looking burned.

The duranta confuses me since not all are droopy. But then only 2 of the 7 oleander are affected, also. Go figure.

But I will do all of what you said to do with soil and plants and see if there are any answers. I'll let you know. Thanks for your help!

[imafan26]

The oleander, crepe myrtle and duranta are pretty tough plants here.

Oleander can handle a lot of different soil conditions and thrive from hot and dry to wet. It is very poisonous though, so you do have to be careful with it.

Duranta just needs to be in full sun to show its' best attributes. It does get attacked by sucking pests, but for the most part it tolerates it fairly well.

Crepe myrtles are street trees, they are messy unless you get someting like Little Chief with is a dwarf that does not really throw seeds. It is probably the fussiest of the three, but also fairly tolerant of neglect. The wood is brittle though and will break in strong winds.

[jeh]

Good to know. Thanks for the info!

[jeh]

Catgrass was right about the duranta. All they needed was water, a LOT of water, certainly more than I'd obviously been giving them. More than I thought necessary which is, unfortunately, a bummer since our water is going to be fairly severely cut/rationed soon here in SoCal.

[rainbowgardener]

RE-USE WATER! We've had several people writing in from drought struck places lately. There are various conservation things you can do to help the soil retain water (lots of organic material, thick layer of mulch), but ultimately if you don't have well established desert plants, you will need to add water.

Suggestions from applestar for water re-use:
(1) when preparing meals, wash vegetables in tubs or buckets of water, so that it can be re-used, not under running water
(2) save other cooking discard water like water from rinsing rice, pasta cooking and veg steaming water (don't use salt)
(3) take a 5 gal bucket in the shower with you (you need to use environmentally safe soap, shampoo and other products)

I'm sure if you start thinking like this, you can find others. If you are used to having the water running while you brush your teeth, use a bowl of water instead.

In the long run, we all need to adapt our houses with some grey water systems. A small fraction of the water we put down our drains would give lush gardens. We are in the process of trying to sell our house and move right now. If we hadn't decided to do that, my plan was to install a little diverter valve in the drain pipe under the kitchen sink. Turn the handle one way and water goes in to the sewer system as always. Turn it the other way and water from the kitchen sink is diverted out to the garden, either directly to some kind of soaker hose system or to storage. Other than getting the pipe from the diverter out through the kitchen wall, it wouldn't be hard to do. The diverter is because here in wet Ohio, I wouldn't have use for all the kitchen sink water. Also if you happen to be putting anything down your kitchen sink that you wouldn't want in your garden, you don't have to let it go out. ... Water from showers, bathtubs, laundry could be treated the same way...

[jeh]

Ah, yes . . . I remember such strategies from another restriction we went through many years ago. There really are a lot of ways to cut down on water use. But I haven't heard of the diverter valve before. What a great idea. I think we'll do that!

[ElizabethB]

Love RBGs water conservation ideas. Driving home in the rain last evening George commented that it was a shame that we could not ship our excess water to drought stricken regions.

Jeh - water is probably your biggest issue. You may think that you amended an area large enough for your plants but probably not. The variation I the condition of your plants may well be soil related. When dealing with clay the density can vary greatly in a few feet of space. One plant will do fine and another plant 3' away will whither.

I am curious to see your test results.

Good Luck & stay in touch.