I posted this info a while back on a thread on scented geraniums, but I thought it was worth reposting in a thread of its own so it would be easy to find. These methods should work on most herb cuttings and probably also on lots of other plants, shrubs, etc.
BTW, I highly recommend Tom DeBaggio's book -- it's the one that got me interested in starting my own plants from cuttings and from seeds, and it's written in a very accessible, friendly, informative manner. Here's the link to my comments on it in GB: http://davesgarden.com/gbw/c/1617/
Here's some advice from Tom DeBaggio on "Selecting & Preparing Cuttings" from _Growing Herbs from Seed, Cutting & Root: An adventure in small miracles_ I did a little editing & paraphrasing, but much of this is directly quoted. (Great book, BTW) I put together information from several sections, so hopefully I covered everything... Here we go!
It takes a healthy stem cutting to produce a high quality plant. The best plants from which to take cuttings hav been getting plenty of sun and are plump with vigorous, new, compact growth. Avoid plants that are wilted or appear stressed in any way... Stems that make the best cuttings are supple and strong but not woody. New growth (soft-wood or herbaceous) is generally best becuase it is most likely to root quickly and to be disease-free & insect-free.
Many guide books suggest using razor sharp knives, but Tom says he has always used sharp scissors, which cut cleanly and make a nice wound that encourages the cells to multiply & make roots.
Selecting the best stems to cut can take time, but it's important to work quickly so that the cuttings don't wilt before they can be stuck & put in an atmosphere of high humidity. Early morning is good, but early evening might be even better with 12 hours of darkness to help the cuttings adjust to their new status.
Try to cut stems to a uniform length, somewhere between 3 and 4 inches, but this will vary with the herb variety and the condition of the stems on the mother plant. It doesn't seem to matter much where you cut on the stem, whether above or below a leaf or root node. The woodier and tougher part of the stem below this tip portion is slower to root, and the longer a cutting takes to root, the more danger it faces from disease. Disinfecting the cutting tool with alcohol after each cut will lessen the possibility of spreading disease form one plant to another.
The best time of year to take cuttings is when plants are growing rapidly, daytime temps are still between 55 and 70 degrees F, and nighttime temps are above freezing. Cool (spring) weather is less stressful to cuttings. Stem tips cut during fall often root slowly because growth has been slowed by approaching dormancy.
Cuttings are extremely vulnerable once severed from the mother plant, and heat and strong sunlight can cause them to wilt quickly, so it's good to move to a shady spot to prepare & stick the cuttings. Strip leaves from the lower half of the cuttings by quicly sliding your thumb & index finger down the stem. It takes some practice to get the pressure just right; the goal is for the leaves to come off without damaging the stems. After the lower leaves are removed, but cutting has a bare stem on the cut end and nice green leaves hugging the stem from the midpoint up to the growing tip. If you're going to root the cuttings in water, do it forthwith.
If you're using a rooting medium, there are many options. A rooting medium should be free of diseases & weeds, hold water but drain well, and support cuttings upright. It shoudl also be loose enough for good aeration & to allow cuttings to be inserted easily. A pH around 6.5 will usually produce the most roots. Tom favors a mixture of one part perlite and one part Pro Mix, a commercial soilless growing medium that contains peat moss, perlite, and vermiculite.
Before inserting the cutting in rooting medium, dip the bare part of the stem in rooting hormone powder... most herbs root easily, so this may be an unnecesary step except for making you feel better psychologically. Use a pencil or a skewer or other "dibble" to poke a small hole in the rooting medium if you like, and insert the cutting, being careful not to bend or break the stem.
Tom usually sticks herb cuttings in open plastic flats measuring 11 by 21 inches by 2 1/2 inches deep and says that between 100 to 300 cuttings will fit in such a container. Any sterile container that is no deeper than 2 or 3 inches may be used to root cuttings. Space cuttings far enough apart that their leaves don't quite touch. Permitting some air circulation lessens the likelihood of disease in the super-humid propagation atmosphere. Pots that are at least 2 inches deep are useful for rooting just a few cuttings, but those deeper than 3 inches may keep the rooting medium too wet for good aeration.
After all the cuttings are stuck, water with a gentle flower to settle the rooting medium around th base of the cuttigns without packing it. After the cuttings are firmed by the water, they go into a high humidity environment.
Cuttings root best when they have some leaves attached to them because the leaves produce chemicals that promote root initiation & growth. On the other hand, too many leaves, or very large leaves, speed water loss that can lead to wilting & quick death. Protecting the cuttings from water loss & wilting by raising the humidity around them is most commonly achieved by regular misting, either applied automatically or manually with a spray bottle each time you walk by your cuttings.
It may be easier to produce a high humidity environement by using a plastic humidity dome over your flat of cuttings, or by placing a pot of cuttings inside a plastic bag. If you use a plastic bag, stick 2 wire coat hanger arches in the pot to support the top of the bag so it won't touch the stem or leaves. Place the pot in bright light but out of direct sun or the temperatures inside the bag will become lethal. Spritz the cuttings each day and close the bag with a clothespin or twist-tie; leave the bag open each night.
As long as air temperatures can remain fairly cool (in the 60's is ideal), it can work very well to place the cuttings under florescent lights for 12 to 14 hours per day (regular cool 40 watt tubes in shop light fixtures work fine, no need for fancy "grow lights"). If you use a seedling heat mat with a thermostat, the ideal root zone temperature for cuttings is between 75 and 80 degrees F. Whenever the rooting medium becomes dry, dampen with water (mixed with small amounts of fertilizer if you wish), but do not soak the medium.
Check your cuttings daily and remove any dead ones promptly to prevent the spread of disease. After a week or so, check the progress of cuttings by tugging them at random to see if there is any resistance caused by new roots. You might pull up a cutting or two to look for a callus, an ugly mass of cells that swells the stem & eventually cracks with roots.
When the roots are from 1/4 to 1/2 inch long, the cuttings are ready to remove from their pampered rooting environment. Don't leave them at risk of disease in the super-humid propagation environment any longer than necessary. The flats may be left on heat mats to encourage roots to continue developing rapidly. If roots are vigorous, flats may be left on a sunny bench in the greenhouse for a few days (or under lights with humidity dome or bag removed) before transplanting to 2 1/2 inch pots.
Transplant cuttings into moist soilless potting mix, keeping as much of the rooting medium with the roots as possible as you move the cuttings. Cut the growing tip of each cutting to encourage it to branch at the same time that it is filling the pot with roots. With most herbs, this producees a nice branched plant in a few weeks.
A couple of additional notes on geranium cuttings. They can be rooted in water, but this may take 3 or 4 weeks. If you root them in water, be certain to change the water *every day* or you risk having the stems turn to mush. Tom notes that letting the cuttings "heal" overnight by sealing them inside a plastic baggie increases rooting for cuttings stuck in rooting medium, but not for cuttings being rooted in water.
This is a great tutorial on cuttings...I just posted one on doing coleus with step by step pictures-if I had seen this I would have included it with mine. Great work!! I hope everyone sees this. Lots of helpful information here-right down to keeping the cuttings uniform in size and removing the bottom leaves, and getting the cutting transplanted soon after it roots.
I think that as you go along, you develop a method that works for you... But I found Tom's comprehensive & detailed description very helpful a few years back when I was just starting with propagating from cuttings, and I still refer back to it if I seem to be having poor luck propagating a particular plant... sometimes it turns out that I'm skipping over one of those fine points!
I've tried other types of cuttings in water but not buddlea... LMK how it works out! In general, I have better luck sticking cuttings of "woody" plants & shrubs in soil than rooting in water. But a couple varieties of pelargonium (scented geranium) have been rooting in water pretty easily for me (about 50% success), and I currently have corkscrew & fantail willow cuttings rooting in big jars.
If I don't want to set up a covered pot for sticking cuttings, sometimes I just put them in water and wait a few weeks, changing the water every couple of days... If they show no signs of rooting, I can always change my approach and pot them up!
Thanks, Jill, I have copied it to my files.
I have tried cuttings on my annual salvia. It grew all winter indoors but died to damping outside. I will learn.
Tigerlily, can you give me the URL to your information on coleus. Thanks, Linda
I have mixed luck overwintering cuttings... some plants just seem to be tougher than others. I had a couple of little cuttings that hung in there all winter, no new growth, and they're still looking pretty runty now that they're planted out. Other cuttings grew into huge plants in their little pots and have now taken off. I'm still waiting for new growth on my overwintered pelargonium cuttings (roots look great, top growth is spindly), but the ones that I kept in larger pots in the morning room are doing fine.
Anna, I'm glad you got Tom's book & are finding it helpful! It's probably the gardening reference I grab most often.
I think part of the key to success with overwintering for cuttings is to give the plant as much sun as possible and still fert-although less than when the plant is actively growing. Some plants don;t want to overwinter-they want their dormancy and thats it as far as they are concerned!
Well, Tom DeBaggio certainly taught me a lot, mostly from his books and partly from talking to him during our annual trip to his nursery. Although there's no question that his early Alzheimer's is a loss for everyone, I'm glad he found ways to pass on his knowledge and passion. When we were there last spring, I told him he'd taught me nearly everything I know about herbs, and now I was trying to pass his knowledge along to folks in this big online gardening community, and we were all having such fun growing and propagating and sharing our plants... I also mentioned that I tried to put in a plug for his book when I could, LOL. He looked a little bashful, but I think he was pleased.
Gosh, that would probably make anyone who knew us both just ROTFL, I think! We both love plants, but our demeanors couldn't be more different... I'm sure he finds me quite silly in my enthusiasm... Tom is actually a quiet, soft-spoken man, and his son seems similar in that way.
But I can't tell you how much I appreciate the compliment! I have about 4 or 5 decades to go though before I gain half of Tom's expertise!
Just ran across this thread which has great info. I've discovered a new (for me) rooting environment: a fish tank or aquarium (mine is 20x10x12 inches) which I cover with a piece of plexiglas with a few holes drilled for oxygen. I place the tank on bottom heat under florescent lighting in my basement which has a fairly constant ambient temperature of 70 degrees. This set-up is particularly useful for larger cuttings that won't fit in a flat with humidity dome and its a lot easier to work with than the plastic bags I've use in the past.
I use a 50-50 peat/perlite mixture with Rootone and mist every day with a little direct watering if the soil gets too dry. By placing the cuttings in 6-cell plug flats or 4 inch pots for larger cuttings I can move the plants out of the tank when they're ready without disturbing other cuttings and the repotting is much easier than propagating in a large undivided flat.
So far I've had great success--almost 100% rooting with a variety of shrubs and perennials. For instance, I started several different types of variegated eunonymus about a week ago and already have new growth on most of the cuttings.
Great idea! I use all sorts of enclosures to increase humidity around cuttings... and you're right, more than a few cuttings inside plastic bags gets to be a nuissance. I think putting a few holes in the cover as you've done is a key to success, as it seems to keep the humidity balance just right.
Can I just poke my nose in here, I'm always looking for ways to propogate more plants (heavens knows why as I have no room left in my borders) I tend to be very hit and miss with mine, so it was great reading your instructions critter, I guess my biggest problem is I'm impatient, and over zelous..when I decide to do cuttings I end up with literraly trays of pots all lined up...But doing this I also accidentally found another 'way' of doing root cuttings.
Last autumn I did the usual, and ended up with three big watering trays filled with sand with rows and rows of pots containing cuttings in.There they stood all through the winter, and grew away this spring, most being potted on, though probably more not...then this summer ,when I went to move some more, to plant them up, I found that the roots had grown though the bottom of the pots into the sand.I cut these off so's I could lift up the pots, not thinking anything of it, then a couple of weeks later I realised that the roots had started to grow tops...these I scrabbled out of the sand, and potted them up, and hey presto, more plants...I'm now going to try it with some Eryngiums, see if they'll do the same, and maybe some poppies..
Oh, very cool! I think it was Michael (michaelsnursery) who posted recently about doing dormant cuttings, taken from shrubs in fall and tucked into the ground (or pots) in a sheltered place... sounds very similar to what you did, although you then got a second round of plants from those orphan roots... I am going to stick some cuttings this fall!
I posted this question on the perennial forum yesterday, but I will repeat it here since you are full of information.
When overwintering, is it better to do a cutting and try rooting, or should I try to dig up the whole plant? I am particularly interested in lantanan, mexican heather, and osteoporum. I have never overwintered anything.
I've never tried overwintering those before, although I do have a lantana in a pot that I plan to let go dormant in the basement (little light, water sparingly once a month)... my neighbor puts his lantana in his garage (unheated but above freezing) over the winter, and they pop up just fine every spring.
I think it mostly depends on space considerations... it's easier to find room for a window box filled with cuttings than for half a dozen larger pots. If you have room for the plant, maybe you could try both methods (take cuttings also) and see what works out. If they all survive, you'll have more plants of a favorite variety... and if the cuttings or the plant do better, you'll know which method to use next time.
Hopefully somebody will have more experience with the varieties you mentioned. If there's not a thread started on overwintering in the perennials forum, there should be! :-)
You can do both-a lot of times, I will dig up those plants-take cuttings off of them, and repot the plants and take more cuttings off of them throughout the winter. I do have a heated grhouse, though.
All those plants that you mentioned are easily dug up and potted (not sure about the osteo-never did that one). If you don't have a grhouse, you could keep them going over the winter, I would think, if kept in a full sun window (south side). Keep on the dry side.
I had been wondering the same thing about lantana. So I've repotted my Lantana "Lisa" and have take cuttings. So hopefully they will all survive. The color of the flower is so different than the others.
Here is a picture of it when it starts to open up.
I just took 9 cuttings of my patriot lantana and 9 of the mexican heather. After planting them in the pots, I had to recut all of them when I re-read your instructions Critter. I guess that I was trying to jumpstart things by using cuttings of seven, eight, and nine inches at least (one might have been larger). Naturally, none of my cuttings would stand up straight because of their size, and the small 3" pots that I was using.
I did recut all of them to around four inches. I still can't get the humidity dome on fully, but I will just have to check on them everyday. Since I expect that these plants will continue to look good for several weeks more, if I make a mistake or just have a poor outcome, hopefully, I will be able to have a second chance.
I'm looking for advice about a cutting of forsythia. I have a single variegated branch on one of my bushes. I want to propagate it but since it is a sport I am afraid to cut it for fear of losing it. Today I put the end of the branch into a pot hoping to get roots w/o cutting it. But I would like to root more than one piece. Is there a way to root other areas of the branch w/o cutting it? I am afraid that if I don't get it propagated now cold weather might mess it up somehow. Does anyone have suggestions & has anyone else ever had an anomoly like this one?
I'm sure someone knows how to do it, but just in case you don't get an answer, why don't you take off one of the non-variegated branches for practice? Someone has listed forsythia on the "very easy to propagate" thread, so I'm betting moist soil will get it going for you. I just don't know if it will if it isn't taken in spring.
I just asked my mom, who has propagated hundreds of forsythia cuttings, and she says she's never cut a branch in half and rooted both pieces, she's just used long tip cuttings. She's also never tried to propagate them other than in spring, but that doesn't mean it can't be done, just that I'm not sure. I had an idea, though... Why don't you take a cutting from the end of the branch without taking off the entire variegated branch? That way, hopefully you'll get a viable cutting and still have a later opportunity to take another cutting if that branch's variegation remains.
These bushes usually root anywhere they touch the ground underneath. That's why I put the end of it in a pot while still attached. But it barely reaches the ground. If I cut off any I will have to sit the pot up on something & I don't know if that would stay in place with the cat, the wind & the neighbor's dog.
PF list several methods of propagation for forsythia that I am not familiar with. "By simple layering By tip layering By serpentine layering By stooling or mound layering"
Can anyone enlighten me? I assume tip layering might be what I did by putting the tip of the branch into soil???
Thanks for the bump, Robin! I'll take some cuttings and get photos... like the clump transplanting post, this will eventually be turned into an article also, combining Tom's techniques and my own experience. :-)
I've been concentrating on seed starting articles this spring.
I root cuttings in a small cold frame in a shady spot in the garden. It is a 4 X 4 box which is about 16 inches in the back and 8 inches in the front. I use a mixture of h alf river ( not play ) sand and peat moss.
For most cuttings you cut on a slant just below the node, dust with rooting harmone and stick the cutting by poking a hole with your finger and then putting the cutting in it. If you have a lot of cuttings to stick justt slit a line with a knife in the sand and stick each cutting that way. do this with roses herbacious perennials and an occassion al shrub.
I rremember working in a farm nursery some 50 plus years ago and watching an old timer filling a whole greeen house bench with taxus cutttings. lHe didn't even use rooting harmone. It still worked !