This season toughest to root are JH Adriatic & Adrina.

For me this season toughest were Black Madeira & Bayerfeige Violetta in fact the B. Violetta still no roots after atleast 5 weeks.

My biggest disappointment is the Enrico.
Been in the bag with moss for two months and still won't root.

R. Latte
 3 sticks busted roots out nicely then 2 just petered out after careful transplant, 1 is at a stall not showing roots in cup.
Have 2 sticks of them in baggie doing nothing and if they continue i will try the ole clonex red gel.
Had a preto show roots in SM cupped it 2 months ago nothing yesterday all of a sudden i see many small roots in cup.
Two jolly tigers i tried to root and they rotted now after i pulled them out of cup, another that was a foot tall i rooted last season never made it thru winter storage , trying to get an extra one of the off parent plant for further observation but that will have to wait for now.
No i dont Root Scion 100% and never will and those that say they do and grow all of them into plants in my personal opinion are full of hot air. My experience has been some difficult scion thats been hard to root in past and replace it with same type will root very easy it just that there all different batches some good some not .

For me it was JH Adriatic, Black Madeira & Sultane which did eventually root. However, JR/GM Sicilian Black, several possible Sicilian black cuttings from El Paso and Sal G.'s White Unknown still show no signs of roots, darn it.

Sicilian black (jr) was a total failure.  I tried a few different methods and only 1 cutting is left.

I don't know why, but I had a hard time with Hardy Chicago and Latarrula.  The HC was generally a poor rooter for me, and I'm on my last one, which I thought I was losing the other day.  The Latarrula rooted really freaking well, it was rooting by the time it got here, was very strong at rooting in the cup, but never broke terminal bud or sent sprouts.  After months in cups, the terminal bud finally started to shrivel, even with proper moisture and environment.

Out of all the cuttings I started over the last 6 months, I have to say, the easiest to root and most prolific (combined) for me was Gino's Black. 

The best, most "explosive" rooter is the "Unknown Voiture #217" that I handed out cuttings of to several people this year, it took forever to pop rootlets in the bag, but when it did, they were rootbound in the cups in less than 3-4 weeks.

The most consistent cutting was Conadria - all varieties I have gotten (3 different - 2 kinds from UCD, one from a solid source in NY).  All cuttings rooted; all survived, even through hardships.

I received one single cutting of Sicilian black, and it is looking good (so far).  I got a lot of single cuttings this year - Banana, Strawberry, Vern's BT...many had excessive top growth prior to roots, and all that did seem to have failed.  I can't complain though, out of the 30-40 varieties, I've only lost 3 at this point (Latarrula, Vern's BT, Banana) with HC looking like it could be a 4th (still hasn't kicked the bucket yet, but I think it may be rotting from inside).

Mine toughest has been barnisotte. Cuttings still look ok but no roots so far. I have had good luck with Black Madeira, Preto, panachee, Col de dam, beall, Hollier, and VDB. Raspberry latte was a slow rooter for me but once it did start putting out roots it seemed to do well.

Oh, if we are talking lack of roots, then Vernino.  All of my UCD cuttings except Vernino are rooted at this point.  Vernino doesn't even look like it wants to start roots.

John Im surprised your hollier was hard to root out of about 50+ varieties I have rooted I would say the Hollier is definately in the top3 of best rooters for me atleast. 

Nelson, the hollier was an easy one. I think you misread my post. The only one I have not been able to root so far this year is the barnisotte but I already have a nice barnisotte tree that I bought last season so it's not too big of a deal if they don't make it.

Sorry John I did indeed misread your post.

I tried rooting three Barnisottes a few years ago from UCDavis, and none of them rooted, just shriveled.

I guess I'm full of hot air, pfffttt!  All of the cuttings I got from Jon have rooted and are growing. I got Preta, Red Italian, Cucumber, Black Madiera Seedling, and Violette de Bordeaux.  But then, maybe these are varieties that root easily. Don't know. I just did the sphagnum moss in the baggie in a slightly warm place routine and potted up into barely moist mixture of perlite/rose potting soil (about 70/30 mixture) leaving the clinging sphagnum moss attached to the roots into styrofoam cups (not clear cups) and only coddled them a little. They have been on the back porch in the fluctuating temps for the past few weeks. Anywhere from the mid-40's to the mid 80's, in bright indirect light with a bit of late afternoon direct light. Kept barely watered, whatever humidity was present outside. It's been a bit dry lately, slightly windy.  So far, it is working well.

Rooting in a Bag, New Style has been fabulous. It is too soon to tell the final numbers, but have lost well under 1% so far, though I am sure others will follow. I think one of the secrets has been burying the cutting 90-95% in the rooting mix, which has eliminated the issue of the cutting drying out. Putting them in an 8 x 8 greenhouse at low 70sF and a fair amount of humidity has provided sufficient fresh air volume and mold has only occurred on 2 cuttings so far (about 1/10 of 1%). Many cuttings show top growth before roots, or simultaneously, but there is enough humidity to maintain plant moisture until roots catch up, if need be. Yes, some are still slower to root, such as Black Madeira, but they rooting and rooting in much higher % than anything I have tried previously. I eve have cuttings 1-1/2" in diameter, 16" long rooting in tall, skinny water bottles that are beginning to show roots after 8-9 weeks, and are beginning to bud out. Black Mission still has a lot of post-potting limpness and failure which will need some further experimentation to correct. Cuttings in the same environment, potted 6-8 in a one gallon pot, with more organic material in the mix have not done near as well, probably because of to much root-zone moisture retention. I don't want to brag, and the rooting season is far from over, but this really has been a revolution in terms of successful rooting, with more success and more promise than anything I have tried.

Voiture 217 would have rooted if left in the open air on the back patio - just crazy. Others were the same way. But, once again, every variety is different and some will continue to try our patience,

I'm going to try the baggie/sphagnum moss method with some greenwood rose cuttings, because I've always heard they root well under mist. Maybe the baggie method will work. Can't hurt to try!

I'm bumping this super old thread to add to and hopefully continue....sorry in advance if resurrecting a 4 year old thread is a bit taboo.  I thought it would be good for newbies like myself to have this thread around for a little peace of mind when their prized cuttings are just sitting there doing nothing. 

From my surfing the forum with the search tool, its apparent that it'll be different for everyone.  Different heat, light, moisture, size and age of cutting, time from tree to rooting media, and time dormant when taken probably ALL influence how well a given cutting roots.  That being said, here are a few notes I've taken on my more difficult cuttings this year.

1)  The Mt Etna strains are awful!  Out of 1 hardy chicago, 2 Marseilles black, and 1 Sal's GS, I've gotten 2 of the 4 to take root (one of which was last week).  For reference, they were all started over 6 weeks ago, some of them over 8 weeks ago.  Out of 25 or so cuttings total, I've gotten all but 4 to root.  2 of them are Mt. Etna strains.

2)  Peter's Honey, JH Adriatic, and Hollier were slow, but as soon as they started, they exploded, particularly the latter two.  JH Adriatic is a super star in my hands once it rooted.

3)  The heat mat makes all the difference...sometimes.  After a cutting roots in a bag, I put it in media and move it on a heat mat at low temp in a big tupperware container.  When they have a few good roots(several inches), I move them up to the grow chamber (big tupperware with lights over it instead of heat mat).  Some of them rebelled instantly, and quit sending out new roots.  After days of no growth, I put them back on the mat, and they exploded with roots.  Other cuttings don't seem to care about the heat mat and continue rooting nicely.  Nero600m is the worst of them...dang thing LOVES that heat mat, but gives up on life the second I remove it.

Finally, never give up on a cutting.  I rooted and then rotted said roots on maybe 10 or 12 cuttings.  I had others that molded, and I had to snip the ends off.  Didn't give up on any of them, and its paid off.  A Marseilles black cutting that I started November 12th just rooted last week.  For some extra inspiration, one of my Atreano cuttings rooted back in mid-late November.  It had nice leaves and a few nice branched roots.  Then I over-watered it and it lost all its leaves, began to mold, and all of its roots rotted off.  About 10 days ago I cut the moldy parts off, cleaned it with soapy water, and tried to re-root it.  Found two little roots on it yesterday :)

Great info.  Good to hear what worked and didn't work Brett.

I can update in a week or two. I just started 3 varieties. Will start a bunch of other different ones over the next several weeks.

I'm glad this thread got resurrected.  Most of my cuttings are nicely rooted except for one nasty variety: Bayerfeige Violetta.  It has been over a month and no signs of even initials...now I have a possible reason.

It is truly amazing how some varieties root for some of us and not others. Nero 600m and Panachee have rooted easily for me but I can not get Native Black to root and it roots with ease for others. My rooting method is not complex or magic, I just stick them in a gallon pot, put them outside in a plastic(make-shift) enclosure and presto, no muss no fuss. I do check on them daily and give them a little drink now and then.  Here are some photos of the 5 Nero 600m
  The other 3 are like this.
 
Photo of temp and humidity

 

Also, Brett, with you bumping this thread gives support against the request by someone to delete old threads. Thanks for posting.

I like it when old threads like this get bumped by further relevant posts.

As for the topic, Black Madeira and JH Adriatic have been two shy rooters for me.  I had no luck with them last year: JHA gave me buds but no roots, and BM didn't do anything but slowly rot.  So far this winter, single cuttings of JHA and Figo Preto are showing initials, but only teasingly so.  I don't want to put all my eggs in one basket, so I've got more JHA and Black Madeira cuttings coming in the mail this winter as reinforcements.  I definitely want to get these varieties going, so hopefully at least one of each will root and flourish.

A lot of members suggest rules (You aren't doing that, I know) but the only real rules come from Jon.  Don't be afraid of violating rules that don't exist.   :)   My opinion is that it's better for future knowledge seekers to keep as much info as possible in a single thread.  Plus it proves you've searched and that should win you points with older members  :)

Now on to the topic.  Some varieties may be harder to root than others but some years produce weaker cuttings than others, some areas produce weaker cuttings (probably because of weather) and some subset of cuttings from different growers may be weaker because of cultivation practices.   A certain grower may produce cuttings with varying vigor depending on cultivation and environmental issues.  Some cuttings mailed at certain times can get too warm inside or too cold outside or spend too much time in transit with too much or too little water.

Sometimes it's the cutting(s).

Sometimes it's the match or mismatch between the conditions supplied by the rooter and the needs of the variety and the particular cutting.  Sometimes a package might sit against a heat vent and the 3 cuttings nearest the vent become non-viable.

There are so many random unknowable factors that you just have to do your best and pray.  I had one batch of cuttings one year in which none of them rooted. the batch before and the batch after did fine.  I don't know of any differences between the 3 batches but there was surely something.

All you can do is watch your water and hope for the best.   :)

Well said Bob, a lot of factors are involved even as you emphasized...the unknowns.

Wayne
I think you can speed up your rooting and maybe success factor if you increase the temperature. 
 65.3F seems a temperature where mold is a little too happy and may compete with the cuttings especially at such a high humidity. 
I find the closer to 80F I can get it without drying out the cuttings the faster it roots.