What is best mulch for rhodos and azaleas?
I have woodchips from deciduous trees in abundance. Are those reccommended?
They have the problem that they host shotgun fungus which will permanently stain houses and fences. Other than that, they should be fine. People say they take nitrogen from the soil, but John Doppel, a rhododendron hybridizer, uses hardwood sawdust for a mulch and has a fantastic garden and remarkably healthy rhododendrons and azaleas.
The plants are not near the building or anything that I would mind having stained so shotgun fungus is not an issue. This is good news since I have the wood chips in abundance.
Do not use black walnut or butternut chips. They contain a chemical that is toxic to most rhododendrons and azaleas. The highest concentrations of the chemical comes from the roots, but the amount in the wood could set plants back and make them struggle.
Here is a link that might be useful: Black Walnut and Butternut Toxic To Rhododendrons
Thanks again, Rhodyman. My woodchips do not have black walnut, butternut or ailanthus wood so I think I am o.k. It's mostly wood from tulip trees, sassafras trees and woody shrubs.
I stuck an unearthed rhododendron into a fresh pile of chips once, didn't get back to it for awhile. It got much greener while living in the pile. So much for chips robbing nitrogen and making your plants turn yellow.
The theory isn't that association with wood chips will harm a plant. It is that the bacteria that rot wood chips and sawdust in the soil use nitrogen. Hence, the soil will become low in nitrogen and not healthy for plants. It is a very slow effect and would need to involve a fair amount of rotting wood, since most all soil has some rotting wood in it.
However, if the wood chips or sawdust is placed on top of the soil as a mulch, it apparently doesn't have very much effect on the soil below. Hence, wood chips and sawdust mulches are quite beneficial. However, for a soil amendment, bark dust is usually used to avoid this problem. Bark is much more stable and rots very slowly.
Pine straw (mulch).
Chamaecyparis nootkatensis 'Green Arrow' - 'The Harper Collection of Rare & Dwarf Conifers'; Tipton, MI.
Pinus strobus 'Sea Urchin' (The Harper Collection)
What canI do ? I have mulched trees , maples and oaks, and what ever else thats put in the towns recycled mulch thats free. I heard that the leaves from the maples , locust and oaks are all thats needed and I hould just leave for the winter. Also , what your opinion and correct way to apply "Hollytone". I heard that this is good for Rhododendrums. But I heard diffrent than some info on the label. They are in a sandy type soil with good drainage also get minimal sun and are fully matured trees
Hello, tommy23. The leaves from your own trees are a great source of mulch. The free recycled mulch is risky since you do not know what has gone into the pile. Unless you can identify black walnut or butternut chips in the pile and remove them, you may just have to get a little mulch from 3-4 different locations of the free pile in other to minimize the risk of getting black walnut/butterbut chips.
You may also want to do what I do... ask the neighbors to accumulate (dump) their leaves somewhere in my property so I can use them as mulch. I have two or three neighbors with pine trees who supply me with quite a lot every Fall. Most goes to acid loving plants. The non pine needles go into the compost pile. Important: if the neighbor has a dog, ask them to be remove the dog's "mineral deposits" first. Hee hee hee!
Hollytone is a good choice for rhodies/azaleas but make sure that you are fertilizing the plants because they need it. Rhodies and azaleas are not heavy feeders like -for example- roses and will do just fine feeding off the decomposing mulch. It goes without seeing thus that you need to keep them well mulched throughout the year.
One application of Hollytone in mid spring should be enough for the whole year. Choose a time frame when the risk of more freezing temps is low. Feeding them then will minimize the possibility of bark split problems.
You can always fertilize much later if you need to or want to instead. But do not apply them after July or thereabouts.
1. Sample soil and have it tested before fertilizing. Use a product that supplies the needed nutrients, if any are needed, in the correct amount.
2. The best time to fertilize hardy plants is the fall. Spring is less favorable.
I second the motion that rhodies and azaleas don't need fertilizing under normal conditions. However my plants are all mature (over 10 years old) and bloom just fine. Where you may want to use a good quality acidic fertilizer like Hollytone is if you want to encourage young plants to get bigger or the plants are showing symptoms of a problem. They are better at showing soil problems than soil test kits. If you want to fertilize or need to fertilize, the best practice is either before blooming or after blooming or both. I pefer the before blooming myself, but I only fertilize about every 5 years. Hollytone has the basic ingredients, but also has trace elements and sulfur to make the soil acidic. It is a good product. If you follow the directions, apply at half the rate they recommend.
Here is a link that might be useful: How to grow rhododendrons and azaleas.