Propagation: Azaleas and Rhododendrons

Okay folks, I've been working hard on this today! LOL Here's some instructions on how to propagate azaleas and rhododendrons. (I know you're happy about the rhododendrons, Dave!) Let's go forth and propagate!!! LOL

Terri


When to take cuttings:
Most evergreen rhododendron and azaleas may be propagated from stem cuttings. Cuttings are usually taken from mid July to early fall (September) from new growth that is just hardening off (known as semi hardwood). Cuttings are taken in the morning when full of moisture.

What kind of cutting:
The wood should be firm and just beginning to brown at the base. To see if your shoot is ready, bend it between your fingers. If it breaks, the shoot is either too soft or too hard. If it's pliable and springs back when you let go, the shoot is at the right stage. The leaves should be mature.

Size of cutting:
Cuttings should be 3-6 inches long. The cuttings are usually terminal cuttings with one whirl of leaves at the top. Take off the bottom half of the leaves (to reduce the leaf area) and any flower buds. The cutting has the end cut off just before placing in rooting hormone powder (containing a fungicide if you wish). Be sure to shake off excess rooting hormone powder.

Soil mixture:
Then the cuttings are placed in a flat of sterile media containing a mix of 50% peat moss, and 50% horticultural perlite or vermiculite. Peat and perlite are probably the best but is expensive. Do not use any fertilizer! You want the roots to have to search for food and in doing so the root mass is larger. Also, new root tissue can be damaged by fertilizer salts. The propagation flat should be 4 or more inches deep preferably. The flat (one that is able to drain) which is now full of cuttings is placed in a clear polyethylene bag with struts (you can use sticks in each corner or a wire hoop) to keep the clear bag away from the foliage and placed in a light area with no direct sunlight. The plastic should not be airtight so the plants can breathe. Cuttings need a protected high humidity environment while they root. Cuttings don't have roots to take up water but they still lose moisture through their leaves. By keeping the air moist, you minimize the water loss and help the cuttings survive until they can support themselves. You can place them in a shaded greenhouse or frame... or on a window-sill indoors. Grow light bulbs can be used to supplement inadequate lighting. But remember... no direct outside sunlight.

Care:
Water with ordinary tap water that is at room temp when needed. Do not let the soil dry out. The flat is rotated once or twice a week to compensate variations in light and temperature. Usually bottom warmth of 75°F is used to encourage root growth. Rooting usually takes about 6 weeks for evergreen azaleas and 3 to 4 months for large-leaf rhododendron. Once the cuttings have rooted, pot or transplant them to flats containing a sterile mix of 60% peat moss and 40% perlite. Fertilize once a month with an acid-based azalea plant food like Peters. Removing terminal buds promotes sturdy well branched plants.

Lisa, since you've done this before, do you see any mistakes? :)

Good! I guess I didn't leave anything out. ;)

Terri

Hey, way to go!! That was fantastic and thanks very much. I shall have to grow a lot of these to fill up my garden but wish I could propagate now because this rental house is full of them.....lol

Terri, I almost forgot. They can also be layered in the ground at any time. So with both propagation techniques we should have bunches of them eh!

Thanks Terri! I'll be doing this and will post my success (or failure) stories!

Of course, I won't be doing it till late summer...

This message was edited Thursday, Mar 15th 9:20 PM

I can't wait to do this!!! I'll tell you what I'm going to do. I'm going shopping for azaleas next week. Now that they're blooming here, I'll be able to select the right colors. I'm buying lots of different colors and the plants I buy will be used just for propagation. When you think about it, we can "visit" lots of different places for cuttings. LOL

Terri

Can almost see you dancing with glee!!

The more Forums I visit on this site, the more differences I see between US and UK/European gardeners. I'd never heard of fermenting tomato seeds, yet it seems to be normal to you.

The most popular method of propagating rhododendrons over here is layering:

Select a low-growing branch, scrape off about an inch of bark on the underside, put hormone rooting powder on the wound. Make a hollow in the ground. Put the damaged part of the branch on the soil in the hollow, put a large stone on top or a loop of wire to hold it down, cover with soil. Leave. When the layer has its own roots, sever from the parent plant.

You're right, Mary! We do have our quirks over here. LOL

People do propagate the way you just described over here, too. I guess if you plan to do about a 100 or so like I'm planning to do, the method I described above would work best. But if you're planning to do less, then the method you described would be easier. :)

Terri

There are a couple more ways you can do mass propagation of Rhodies or Azaleas.....One way is to cut new growth along the length of the stem (a couple of inches) and insert a wooden toothpick into the cut, apply rooting hormone, pack with wet moss and wrap the area. Hope this helps......

Weebus

Thanks, weebus! How long do you usually have to leave the moss on? :)

Terri

If anyone is interested, on the American Rhododendron Society page www.rhododendron.org (Sorry I don't know how to do the link thing), there is a form to fill out for a free rhododendron and azalea care kit. I just sent for mine, so I don't know what's included. But I know, I can use any help I can get!!!
Debbie

Thanks for the info, Debbie! :)

Terri

Hello,
Does anyone know if this will work for Camellias? Sounds like they are very similar. I am very interested as someone just brought me cuttings yesterday and I have no idea of how to root them.
Melody

Hi Bfreakymonkey and welcome to DG! :)

Here's some info on the different propagation methods used for camellias. There appears to be several methods to choose from:

http://www.camellias-acs.com/culture.html

Terri

Thanks again, Terri!
Melody

Sorry it took me so long to get back....... I wrap mine with clear wrap and wait until I see roots. I usually do mine in August and not worry about it again until March/ April. You can also cut your new growth off a little below the place where there is a leaf or a new bud of a leaf forming. Tear of the last set of leaves, dip it in rooting hormone (not necessary but Insurance is a good thing) bury the bud or place where you tore the leaf off. You can root hundreds at a time doing that. they should be miniature looking Rhodies sticking straight up put out of the ground. It is SO EASY that my mother used to break a stick off and poke it in the ground and water it. That's it and it would grow into a bush. No kidding. Still amazes me.

Weebus

Thanks weebus! :)

Bumping a very old thread.

Any other suggestions on rooting azaleas? I use layering on my own plants, but that isn't possible on cuttings from other people's plants.

I have used the method Pete2 describes, but the cuttings always get moldy and the leaves fall off.

if you see something you really like, ask, promise you won't damage the shrub and will trade or share. also, will call before you come to cut the plant loose and so far,i've never had anyone to refuse .i got a beautiful gold streaked with burgandyish brown a few years ago.moved out of state and didn't get a start of it.kick me!!

Digger -- you are probably right -- it never occurred to me to layer someone else's plants, but the just putting a stone or brick on a lower stem is so effective and very unobstrusive.

yeh, happy, and if you explain all this to them, you get a yes,and if they see how desparate you are to have a beautiful plant like thiers,they might be interested enough to (let) you teach them how to do it.give it a try and good luck! all they can do is say no. sally

Makes perfect sense. A lot of the nice plants in my area (Washington DC) are at embassies and other places that clearly have gardeners -- so no one there on a day-to-day basis gives a hoot. But I might try to surrepticiously place a stone just here or there on top of a stem to see if that will do the trick!

i have several plants,among them,an oak leaf hydrangia from the courthouse yard in town.the judge gave me permission to collect everything.caught him having a cigarette out side,and started a conversation. sally

dumb question here...is it the same method for deciduous azaleas?

Depends on the method that you are thinking of using. Evergreen azaleas root and transplant more easily. Deciduous ones can be a liiiitle more difficult to propagate from cuttings although the layering method should be easier and should produce a new plant capable of being transplanted in about 24 months.

To propagate from cuttings, try to take a 3-5" cutting while the wood is still soft, as the capability of propagating decreases quickly as the cutting is more woody. For example, now may be a good time. Dip the cutting in a medium strength growth hormone with fungicide, store in a 60-40 potting soil made of peat moss and horticultural perlite while keeping the bottom warm around 75 degrees F. Transplant the rooted cutting in August to a place where you can provide 14-hr light warm cycles in order to maintain growth. As new growth matures, move to a cooler location to theeeen induce dormancy through Spring 2009. Transplant into a pot and place them in a bright shaded location.

Luis: Do you do your rooting inside then? Or is the first part outside (the rooting), and then do you move it inside for the period of 14-hr "light warm cycles"?

You need to root them inside. A green house would be ideal for this but I do not have one.

That's interesting. I understand many people here do it outside. I have so far been unsuccessful both inside and out (!) unless I layer the plant which always works.

I just put a big rock on a lower branch that is touching some good soil and wait until next spring. Then sever from the parent and plant the sucker! But, I'm not trying to grow hundreds of them. I have found that you get larger older starts this way. Exspecially if you root a large branch. I did this and got one that was 4 feet tall and 3 feet wide as a a new start. But, the original mother plant was large anyway.
Char

Char: That's the only method that works reliably for me -- and it requires zero work!

I live on the Queen Charlotte Islands, NW BC. (near Alaska)
I am SO EXCITED!
Today I had a huge old Rhodo transplanted to my yard because the new owner was going to cut it off to get rid of it. So I hired a Bobcat and he moved it across town for me. We have it in an ideal location, with a small gravel water seam about 18 " below the plant and loamy peat soil. That's all good, and the plant is green and healthy.
The questions I have are:

1. Its on the edge for moving a Rhodo here, its still -1 C overnite... should I protect the Rhodo from drying winds? I do for tiny ones but this is at least 10 feet across and 6 ft tall & symetrical. Its amazing. (Mauve flowered)

2. I would like to shape the Rhodo, it has some odd sticky-ups (3) old branches. Should I wait a few weeks or do it now.

3. Can I over-do the watering, or is there no such thing for a transplanted RHodo. We do live in a Rainforest, but its not esp. wet just now... more windy.

4. We planted it a little deeper than it was before... any imput on that?

Thanks guys, This is kind of an expert question I know, but interesting.
My other Rhodos are gorgeous in a similar location and I do pretty much nothing to them now. They are about 30 yrs old, this one is at least 50yrs old.

Hello, enyeholt. Congratulations on your new plant; sounds very exciting.

Suggestions: Normally I would have tried to move it one or two weeks after your average date of last freeze in Spring but I understand that is not always possible. So, if the temperatures get cold again, I would put some burlap on top and maintain the root ball moist by watering the soil, not the leaves. Of course, if it is a big ole' shrub, you might as well let it be.

As far as pruning, I would do that after the shrub has bloomed. As for planting height, I would plant it higher -about an inch- than the surrounding soil, not lower, and I would not top it off with excess or loose soil. I did that by accident to a native azalea years ago and it did not make it. Of course, mulch it well when you are done.

Expect it to behave as a brand new rhodie would in the summer so keep an eye on soil moisture during the summer; water only when the soil starts to feel almost dry or dry. Add no fertilizers (if you must, only use weak ones like liquid fish or liquid seaweed; coffee grounds are ok but stop them all in early July). Plants suffering from transplant shock should not be fertilized and stopping all fertilizing in July makes sure that no new tender growth will get zapped when winter returns.

For more information on planting, see: http://www.rhododendron.org/planting.htm

Luis

Hi, I was looking for info on propagating rhododendrons because I am going to lose three huge, beautiful old shrubs due to foundation repairs. I have done the burying a lower limb before but needed some other method. I guess the cutting method won't work till later and they will probably be gone by that time. Looks like I will have to buy replacements but this looks like a very interesting forum anyway.

Usually the best time to propagage is in early July; it sounds as if you can't wait that long. You could try cutting off some small branches, sticking them in decent soil and putting a jar over them -- and crossing your fingers. I find them hard to propagate, except for the burying-a-lower-limb approach.

Thanks, I am going to give it a shot since I have nothing to lose by trying

Its been awhile since I got back to reply. Thankyou for the info luis_pr.

Especially I appreciate the tip about not fertilizing while it establishes itself.
It's too late to plant it higher, but it seems happy... I haven't back-filled in the soil except to the root ball, and its on a slight slope so I'd guess that's why I got away with placing it deeper.

My Mauve Rhodo bloomed well, and I have now shaped it. There are some leaves turning red & dropping, but they seem to be the ones damaged in moving it, so far.

I am amazed at the resilience of this bush. It deserves a medal, and so does the friend that moved it for me.

Is there such a thing as growing azaleas or rhodedendrons from seed or do you need cuttings? I love them both and here in the mountains I could have nice rhodedendrons. They never did well down the bayou. The azaleas grow like crazy in the deep south and I'd like to get some for my new house here.

There is such a thing but, if you want to produce another shrub just like the original, seeds would not necessarily do that. Cuttings would.