Multi-rootstock avocados?

[barath]

There's been a lot of great discussion about multi-rootstock trees in other threads, but I haven't seen much discussion of multi-rootstocking of avocados.

My motivation for multi-rootstocking avocados is mostly to produce a stronger tree that can withstand greater drought (at least I'm hoping that's the case).  My secondary motivation is that it might produce a more precocious and dwarf tree, but I don't know if it'll have that effect.

I've tried it a couple of times (last year) by approach grafting two Avocado seedlings (one Mexicola seedling and one Zutano seedling) together and then grafting on the top of the main one.  One one graft of this sort took, but after some time both the rootstocks showed some sort of incompatibility where there was a constricted band below the approach-graft union, almost as if I had tied some tape around each of them too tightly.  Eventually the tree died.  I haven't tried Simon's single cleft on two rootstocks approach (which has worked for me as well with Mangos).

Has anyone tried it, and what method was successful?  Did it matter what rootstocks were used?

[DimplesLee]

I have no actual experience doing a multi-rootstock Cado but if I remember correctly one of the lectures I attended mentioned a Mexican rootstock to Mexican scion is good, Guatemalan RS to Guatemalan S, West Indian RS to West Indian S, and that Guatemalan x Mexican hybrid rootstock could go either way if you are going to be using GxM scions or Guatemalan or Mexican scions only but that is all what I remember of the theory.

Actual experience from the other TFF members would be more helpful for your case.

[barath]

I think most Avocados grown commercially in California are Guatemalan x Mexican (e.g. Hass) or straight Guatemalan (e.g. Reed) grafted on Mexican rootstock (e.g. Duke 7, Dusa, Toro Canyon).  I've had pretty good luck using any rootstock with any scion, though I haven't tried any West Indian types.

[shaneatwell]

I think most Avocados grown commercially in California are Guatemalan x Mexican (e.g. Hass) or straight Guatemalan (e.g. Reed) grafted on Mexican rootstock (e.g. Duke 7, Dusa, Toro Canyon).  I've had pretty good luck using any rootstock with any scion, though I haven't tried any West Indian types.

I thought the established groves were mostly on Zutano?

[barath]

I think most Avocados grown commercially in California are Guatemalan x Mexican (e.g. Hass) or straight Guatemalan (e.g. Reed) grafted on Mexican rootstock (e.g. Duke 7, Dusa, Toro Canyon).  I've had pretty good luck using any rootstock with any scion, though I haven't tried any West Indian types.

I thought the established groves were mostly on Zutano?

No idea.  I know that many nurseries use Zutano, and that's what I've been using.  I got the sense from talking to a few San Diego nurseries that clonal rootstocks are more common now, but no idea.

[JF]

I am very comfortable using West Indian race as rootstock here in Socal I've had great results. The rootstock is vigorous and is just resistance to phytophthora as clonal rootstock

[socal10b]

I got great results with triple rootstocks on my multigrafted tree.

[simon_grow]

I would add at least one rootstock that is resistant to phytopthera. I think multiple rootstock Avos are a great idea, it may help with alternate bearing for varieties prone to it. Please keep us updated. I would love to see some pictures. I love multiple rootstock trees!

Simon

[barath]

I got great results with triple rootstocks on my multigrafted tree.

Interesting!  I'd be very interested to hear what grafting technique you used and what rootstocks you used.  Would you be able to share any pictures?

[fyliu]

LaVerne doesn't use global rootstock. They're grafted onto seed sprouts. Not sure what kind of seed.

[barath]

LaVerne doesn't use global rootstock. They're grafted onto seed sprouts. Not sure what kind of seed.

Yeah -- I heard it was Zutano, but I'm not sure.  I can see why Zutano is generally popular -- it produces good thick stems for grafting, is vigorous (sometimes too vigorous), and germinates consistently.

I got the sense that the nurseries that sell to big box stores use seedling rootstock whereas the ones that sell to commercial orchards (more often) use clonal rootstock.  Here in Northern California the clonal roostocks haven't worked out that well (Ellen from Epicenter Nursery tried them out a couple of years ago but from what I heard they didn't do that well).

[ricshaw]

I got the sense that the nurseries that sell to big box stores use seedling rootstock whereas the ones that sell to commercial orchards (more often) use clonal rootstock. 

That sounds about right.

See commercial grower Brokaw Nursery;
http://brokawnursery.com/rootstock.html

[Samu]

I am currently happen to be experimenting some sort of double rootstock grafting on avocado, primarily encouraged by what the benefits that I read elsewhere and here; also Simon's successes have been encouraging to me.

I did try the same method Simon used, once on mango, but graft didn't take and died for reason unknown to me. (I think it's because of my sloppy wrap.)
So, a couple weeks ago, I tried a little different method on avocado, (running out of mango rootstocks)  I spliced both sides on the scion to meet 2 slices of the 2 rootstocks. 

Don't know if anyone ever tried this method, but I thought doing this way will give me a better change of the graft to take (double sided contacts), but wrapping those 3 branches together is not as easy as doing a regular cleft graft...I found out!
So, I am still waiting the result of this, I'll let you know the outcome in a few...(weeks?)...knock on wood! 

[kingoceanos]

So far I've only done cleft grafts. I tried hass seedlings and the local Mexican avocado seedlings,(not Mexicola). They never worked out for assorted reasons, admittedly some of it was me, (bad eyes and hands aren't as steady as they used to be . What has worked out the best for me strangely enough is the seeds from the Slimcadoes sold at my local grocery store when in season. Personally I only like them in salads but for grafting they are large seeds with a lot of energy and have worked out very well for me. Just out of curiosity has anyone tried the Mexicola and would you recommend it as part of your collection?
Thanks

[simon_grow]

Sam, did your graft take?

Barath, I re read your objective and to increase drought tolerance, I would suggest planting seeds directly where you want your avocado tree and then grafting the seedling when it is large enough. A fully intact taproot may be beneficial in drought. I would actually plant multiple seeds of different Avocado varieties trying to include varieties that may be resistant to Phytopthera. If you get a couple seedlings close to each other, try a double rootstock graft. An in situ grafted avocado with two fully intact taproots may be a good option to increase drought tolerance.

Simon

[barath]

Sam, did your graft take?

Barath, I re read your objective and to increase drought tolerance, I would suggest planting seeds directly where you want your avocado tree and then grafting the seedling when it is large enough. A fully intact taproot may be beneficial in drought. I would actually plant multiple seeds of different Avocado varieties trying to include varieties that may be resistant to Phytopthera. If you get a couple seedlings close to each other, try a double rootstock graft. An in situ grafted avocado with two fully intact taproots may be a good option to increase drought tolerance.

Simon

Hi Simon,

I have been direct seeding a bunch of Zutano and Bacon seeds recently for a public fruit tree planting, though I don't know if they will grow close enough together to be easily double rootstock graftable.  I am hoping that they germinate well here -- we don't have quite as much warmth during the spring as you do, so I'm hoping that the warm weather coming up this week combined with the rain we've gotten will get them sprouting and give them a chance to sink deep taproots.

[socal10b]

I got great results with triple rootstocks on my multigrafted tree.

Interesting!  I'd be very interested to hear what grafting technique you used and what rootstocks you used.  Would you be able to share any pictures?

Sorry for the delay, i will post pics later, triple rootstocks make everything grow faster. I planted fuerte seedlings right next to my sharwil and graft them to the trunk,and i top worked my sharwil last year with Carmen, sir prize and lamb. My triple rootstock tree is ready to hold fruits.

[fyliu]

So you did in-arching to attach the new rootstocks? I have an avocado that's been chilling at less than 5 ft for the last 3 years.

[Samu]

Sam, did your graft take?

Barath, I re read your objective and to increase drought tolerance, I would suggest planting seeds directly where you want your avocado tree and then grafting the seedling when it is large enough. A fully intact taproot may be beneficial in drought. I would actually plant multiple seeds of different Avocado varieties trying to include varieties that may be resistant to Phytopthera. If you get a couple seedlings close to each other, try a double rootstock graft. An in situ grafted avocado with two fully intact taproots may be a good option to increase drought tolerance.

Simon

Hi Simon,
I've been checking it for the last 3 weeks or so, didn't see any leafs coming out ...from eye level standing up. Now that you asked, I lifted the pot and observed closely...it looks like the buds are swelling up now, the top one top looks like already breaking the parafilm! Don't know why this graft took longer than my other regular avocado graft to take..., probably it's due to my sloppy wrapping again...

In a couple of weeks or so, I plan to plant this thing in the ground -provided the graft is still alive- before the tap roots encircles the pot; and hopefully it will grow to a stronger and more productive tree!

Again, thanks for this avocado direct seed planting/double rootstocking grafting idea I learned from your postings!

[simon_grow]

So you did in-arching to attach the new rootstocks? I have an avocado that's been chilling at less than 5 ft for the last 3 years.

Hey Fang, if your avocado is not growing fast enough, try this:

http://tropicalfruitforum.com/index.php?topic=12844.0

Thanks Sam but I got the idea from the video I saw. I'm glad more people are testing out multiple rootstocks. I can't wait to see the data in the coming years!

Simon

[socal10b]

So you did in-arching to attach the new rootstocks? I have an avocado that's been chilling at less than 5 ft for the last 3 years.

yes fang, that's exactly what i did to my weak sharwil rootstock. I think u have a very weak rootstock if your tree isn't doing anything after 3 years. Fang, what variety is it?

Triple rootstocks close up


after i added 2 more rootstocks, my tree was being to take off.


sharwil bloomed, and didn't set any fruits.



Decided to top worked it last year



Carmen and lamb are blooming and hope to get some fruits

[Vernmented]

I got the sense that the nurseries that sell to big box stores use seedling rootstock whereas the ones that sell to commercial orchards (more often) use clonal rootstock. 

That sounds about right.

See commercial grower Brokaw Nursery;
http://brokawnursery.com/rootstock.html

This is very interesting. I haven't tried to air layer avocados before but I am guessing it doesn't work if they go through all this trouble to produce rootstock. This is also beneficial because it removes that gnarly taproot from potted plants.

[simon_grow]

Anyone have updates on their multiple rootstock Avocados?

Socal10b, how is your triple rootstock Cado doing?

Simon

[socal10b]

Anyone have updates on their multiple rootstock Avocados?

Socal10b, how is your triple rootstock Cado doing?




Simon

Out of control lol. Carmen hass is blooming again. I will post a pic later when I get home.

[socal10b]

This is how my triple rootstocks avocado tree looks like now



blooming again


Fruits from Jan blooms

[simon_grow]

Wow, the tree is beautiful and looks extremely healthy! Great job on this tree, do you have both A and B type flower varieties on this tree? Thanks for the update!

Simon

[socal10b]

Thanks Simon, and yes this tree has sir prize (B), lamb hass and carmen hass.

[barath]

That does look great!

I'm curious how big the main trunk was when you did the approach grafts.  And how big were the seedlings you were grafting on?  Did you wait until the approach graft healed before chopping off the seedling's top growth?

[ScottR]

Socal, that is one beautiful avocado tree you gotten really nice growth on that multi-grafted baby! I've multi-grafted older trees my top working and has worked well. But really like multi-root stock approach I'll have to try that!  

[xshen]

This is how my triple rootstocks avocado tree looks like now



blooming again


Fruits from Jan blooms

I've watched this tree grow over the last few months and the benefits of multiple rootstock is phenomenal.

[Samu]

Congratulations John, that is a very heathy avocado tree!
Meanwhile, my doublerootstocking avo single experiment failed, the small sprouts
that broke the tape didn't continue pushing and the scion eventually dried up, even though
both rootstocks are still alive. (I may try again later).

Last week, I started an approach graft -also my first- of a Fuerte seedling to a young Sir Prize,
I have doubt if this will succeed since the thickness of the Fuerte seedling is much skinnier compared to the Sir Prize tree, so I'll wait and see...

[simon_grow]

Socal10b, can you post some updates on your multiple rootstock avocado? Any additional info you can give regarding production and growth will be greatly appreciated. I am considering planting out several multiple rootstock avocados at my friends place. Thanks,

Simon

[Samu]

Last week, I started an approach graft -also my first- of a Fuerte seedling to a young Sir Prize,
I have doubt if this will succeed since the thickness of the Fuerte seedling is much skinnier compared to the Sir Prize tree, so I'll wait and see...

Well, almost 2 years later, my approach graft took - to my surprise! - , this is what it looks today:

This is how I started it in Summer 2016:


My tree gave a single fruit in 2015, didn't flower in 2016; some 15 fruits total in 2017 , now it is blooming. So, yes, I am hopeful that this approach grafting can help make this tree a regular annual bearing one instead of an alternate bearing variety...(which some had said).

Not sure of its impact on the growth though, since the tree would naturally grows on its  own (without the additional approach graft), but I notice a "faster" growth on one Fuerte scion I placed on the upper trunk; that I had since topped off about 2 ft of it last week. 

[socal10b]

Hi simon,

I will post some pictures of my multi rootstocks avocado when I get home today. Carmen hass is out of control, needs to be pruned constantly and it has a lot of fruits too.

[Vernmented]

I have a double root planted out that is growing like crazy. I haven't grafted anything to it yet. I have been waiting to get my trellis installed for a little espalier action. I have some other double root plants in root pruning pots waiting to be grafted. They seem to be doing really well.

[simon_grow]

Sam, please keep us updated on your tree. The graft looks great and the additional rootstock looks like it’s grown so much. Hopefully production will pick up once your tree gets a little larger.

Socal10b, can’t wait to see the update.

Vernmented, are your double rootstock trees all seedling trees? Let’s see some pictures!

Simon

[socal10b]

Here you go Simon. My carmen hass is  fully loaded with fruit and still out growing sir prize and lamb hass. Roostock has been buried in the soil.

[socal10b]

I grafted a GEM back in summer of 2015, it is a compact and slow grower. GEM has 6 rootstocks. I will let it carry fruits this year.

Grafted on young seedling


Planted it in the ground after it took


Now

[Vernmented]

Here you go Simon. My carmen hass is  fully loaded with fruit and still out growing sir prize and lamb hass. Roostock has been buried in the soil.

How deep did you bury the root crown? I have been experimenting with this and having good results. So far I have only done things that root easily like pomegranate, dragonfruit and figs. I am going to try Jackfruit and annonas next. I have been obsessed with this since I read this article a while back.

http://rfcarchives.org.au/Next/CaringForTrees/DelayedIncompat9-96.htm

[barath]

Just wanted to add my experience with a double rootstock Sharwil.  I did something like a double stone graft with a double width Sharwil scion, and it has been growing well, but strangely -- short internode spacing, and now, just about 9 months after grafting, at a height of maybe 1.5 feet, it's flowering heavily.  So it does seem to impart precocity and change the growth pattern.

[simon_grow]

Thanks for the info Barath! The more information we can gather the better we can advance our hobby to the next level. So far there has been a couple people that seem to have positive results with double rootstock avocados but i’m as interested in the failures as I am with the successes. Has anyone done a double rootstock avocado that has died or perhaps one of the seedlings died?

If Double rootstock Avocado are truely more dwarf or shorter in stature, more disease resistant(Phytopthora) , more precocious or less prone to alternate bearing, this can be game changing. Even if just one of these variables is achievable, that is an advancement we can be proud of.

Simon

[barath]

I had a double rootstock avocado die when I did it with an approach graft.  I had Mexicola and Zutano seedlings in a large pot together and approach grafted them.  It did fine for a while, and then I grafted a Greengold scion on the top (which was the Zutano top).  Eventually, though, the area just above the approach graft started showing weird growth restriction, almost like it got restricted by a tight string.  Eventually it died.