The Year of the Fig

There are a lot of sites you can find that talk about this in more detail, but I wanted to give some quick guidelines on harvesting scion wood. This will be useful for the AZRFG scion exchange on Feb 4, where we can all trade a nice variety of scions for grafting. Many have talked about grafting, and here is how you want to harvest it and store it so that it is ready for you in the spring.

NOTE: This list is for deciduous scions only. Subtropical scion wood is handled very differently.

IMPORTANT: Make sure your tree is healthy and disease free if you harvest scion wood from it! If your tree is diseased (bacterial canker, oozing / open wounds, etc.) these diseases can be present in the scions that you harvest and they will be transmitted to an otherwise healthy tree when it is grafted on. You must make sure that your trees and scions are healthy to help minimize the transmission of tree diseases.

Wait until the tree has entered dormancy before harvesting. In Phoenix this is typically the second half of December. The tree should have lost all its leaves and all buds should be closed, dark and small. Dormancy here is typically mid-Dec to mid-Jan. But don't wait too long! My Floridaprince peach for example is usually blooming by mid-Jan.
Suitable scion wood will be between 1/8" to 1/2" in diameter. Anything smaller or larger will be too difficult to cleft graft. You can do chip budding with larger diameter wood. But sticking with this size range is good for nearly all grafting applications.
Harvest scion wood with a clean sharp disinfected pair of pruners.
As a convention, many grafters will trim the scions so that orientation is obvious. A flat cut is used to indicate the base end (toward the trunk) and a slanted cut is used to indicate the top end (toward the branch terminal). It is typically easy to see which way the buds are facing, but cutting in this manner makes the scion "direction" easy to identify.
Store scion wood in a heavy duty ziploc bag (the thick freezer bags work well). Take a piece of lightly damp paper towel. Basically add a little water and wring it out until no more water drips. Wrap your scions in the towel and stick in the bag. This will prevent scions from drying out.
LABEL YOUR BAG!!! You need to know your variety.
Put the bag in the refrigerator, NOT the freezer. Put in it the bottom of the fridge, and it will stay there for months.

If you follow these steps, you will have fresh wood that is perfect for grafting in the spring.

I gave a set of small talks (15 minutes each) and demonstrations about rooting cuttings at the AZRFG meeting Thursday night, in preparation for our upcoming Scion Exchange on Feb 4. While this applies to rooting dormant cuttings in general, the method that I discussed works particularly well for rooting fig cuttings.

David Rosenberg gave me a bunch of Nixon Peace / China Honey fig cuttings to propagate. So I thought I would take advantage of this batch to take a bunch of pictures of my rooting process to go along with the written process that I developed for the handouts at the meeting.

You can find the written (printable) rooting process here

Below will be the same process but with a little more explanation for each step (the link above is a more concise How-To) with some pictures that will be useful. For rooting fig cuttings below, read the "Advanced Method".

PROCESS FOR ROOTING DORMANT DECIDUOUS CUTTINGS (DETAILED WITH PICTURES)

Mark Barton
AZRFG
Jan 15, 2017

The processes described here apply to winter (dormant) rooting of deciduous cuttings. Cuttings must be lignified (woody or hardened growth, no green growth) and dormant (cutting must have shed all leaves and all buds / growing tips must be closed, not green, and not swollen / ready to open).

These methods apply particularly well to dormant fig and pomegranate cuttings

These are also methods that are geared toward the backyard fruit enthusiast doing small number of cutting propagations. For growers that do large quantities of propagation, there are more sophisticated methods like perlite-moisture beds or misting chambers that require more intense investment. Those methods are not covered here.

You can also root summer deciduous cuttings (actively growing with leaves) and subtropical cuttings (e.g. Barbados Cherry and Peanut Butter Fruit root very easily from cuttings) but it requires a very different method involving humidity bins and bright indirect sunlight. The procedures below DO NOT apply to this rooting method.

Note before the processes:

Two rooting methods are described below ranging from minimal effort to significant effort. There is nothing rigid about either of these. Most every step can be considered optional. If you want to go with the Advanced Method but you don’t have all the equipment, then skip those steps. Cuttings really only need moisture, drainage and a medium to grow roots into. Experiment and find out what works for you and what gives you a rooting success rate that is acceptable to you.

EASY METHOD

Advantage: Requires no equipment, just cuttings

Disadvantage: Very low take rate

Why you would use this method: If you have a lot of cuttings of the same variety and you want to propagate trees but not invest much time/effort and you don’t mind losing a lot of cuttings (you are relying of sheer volume to generate a set of viable trees).

Take dormant cutting
Stick in the ground or pot
Done

Believe it or not, some cuttings (based on readiness of the bud, moisture level of soil, just the right compaction around the cutting, etc.) will take with almost no effort and almost explode out of the ground all by themselves. But this is not the ‘average’ response to simply sticking cuttings in the ground. Most will rot, but a small percentage will take.

ADVANCED METHOD

Advantage: Can get really high rooting percentage (>80-90%) with nice root systems that turn into viable trees (>70-80%)

Disadvantage: Requires much more time and a modest investment in resources

Why you would use this method: Say you can only get a limited number of cuttings (1-2 of each variety of interest) and you really want each one to ‘count’ (have a good chance to become a viable tree)

Materials Needed:

Cuttings
Bleach
Dish Detergent
Clean soft-bristled toothbrush
Sharp knife (like a grafting knife)
Liquid Rooting Hormone (like Dip-n-Grow or Clonex Rooting Gel)
Coco Coir
Parafilm or Buddy Tape
Sharpie
1 gallon heavy duty freezer bags
Black plastic garbage bag

Process:

Cuttings should be dormant and hardened (the cut end(s) should not be fresh, otherwise it will rot). Let the cutting sit in the refrigerator for at least one week for the cut end(s) to close off and dry out naturally.

When you store the cuttings in the refrigerator you want to wrap them in a lightly damp paper towel inside a plastic bag to prevent the scion from desiccation. In fact all scions for either rooting or grafting should be stored in this way (or otherwise prepared to prevent desiccation) to preserve freshness and viability.

It is advantageous to doing your rooting of cuttings all at once. If you have been collecting cuttings from multiple sources over the winter, or if you get a single batch all at once (like below), then you can do this rooting process sort of like an assembly line, which will definitely save overall effort. The dormant cuttings will stay fresh in the refrigerator for months, so you could (for example) collect your cuttings from Nov-Feb and do your rooting in March.
Make a bowl of cleaning solution. This is simply warm soapy water
Make a bowl of sterilizing solution. This is a dilute bleach solution (1 part household bleach : 10 parts water).
Take your cuttings and gently clean them (do not damage the bark) with the soft-bristled toothbrush with the cleaning solution. Then dip and agitate them in the sterilizing solution. Idea here is to remove any foreign soil, bacteria and mold spores on the surface of the cutting that might cause it to rot while rooting.

Sterilizing solution, cleaning solution and cleaning "tool"
Place cutting into a container (like a lasagna dish) of water so that the bark can hydrate before rooting. Leave in 30-60 minutes.
Take your knife and scrape away 2-3 small lines of bark at the bottom of the cutting. Basically take your knife and scrape the bark with the *edge* (not tip) of your knife gently toward you along the axial direction of the cutting. You want to remove just the bark but *not* the cambium. If you do this successfully you will see a bright green line of the exposed cambium (if you cut too deep you will see the wood). The idea here is to expose the cambium selectively along the bottom of the cutting for root generation. I have found more often than not that this process generates a higher density of roots at these locations.

Sharp knife for scraping away bark / exposing cambium

Exposed cambium (bright green).
If the cut was too deep, you would see white instead of green

But as mentioned above, it is important that you don't cut too deep and expose the wood, otherwise you are opening up / wounding the cutting and exposing that fresh and uncalloused wood as a possible infection site.

MBVS cuttings from Jan 2016.
See the line of roots forming along scoring locations.

Closeup of roots forming along the line from the scrape location
Wrap the top half of the cutting with Parafilm or Buddy Tape. This will prevent desiccation of the top of the cutting as it is leafing out after the rooting process is complete. In AZ in particular, the ambient environment is very dry and the cutting will dry out, even through the bark, once the cutting is out of the rooting environment. This is especially true if you are rooting in March and you transfer your plants outside after they establish roots to take advantage of the warm (75 F - 85 F) spring temperatures. But if you don't do something to prevent desiccation your cuttings will most likely die.

Also, wrapping them now is much easier than wrapping them after they put on roots.

Cuttings with the top half wrapped in Parafilm

It is important to label your cuttings

LABEL YOUR CUTTINGS. You can use the Sharpie to write directly on the Parafilm.
Prepare your rooting solution. If you use Dip-n-Grow, a 1:7 – 1:10 ratio of hormone to water works well. If you use Clonex Gel, you can use it straight as-is. Dip the bottom 2” of the cutting in the rooting solution.

Dip-n-Grow diluted 10:1 (water to rooting concentrate)
Re-hydrate the Coco Coir. Take a block and soak with water for 30-60 minutes. You want to squeeze out the coir so that that no water drips out of it when you squeeze a handful of it. It should be moist but not dripping wet.

Coco coir is a by-product of the coconut industry. It is simply husk fiber that has been chopped, compressed and kiln dried. You buy it in blocks and it re-hydrates in a 4-to-1 volume expansion.

Coco coir in a compressed block

Re-hydrated coco coir

Mix is very loose and light

I have used coarse perlite, sphagnum peat moss, orchid moss, and coco coir (and each in various combinations) and I find that straight coco coir is the best rooting medium. It holds moisture, is a loose mix so their are little voids so that the mix stays aerated, and the mix is light so that roots have very little resistance when they do start to push.
Place the cutting(s) and coir in a 1-gallon heavy duty plastic bag (like a freezer bag). You want each cutting to be surrounded by coir so that when roots form they have some space to grow.

There are 26 cuttings in this 1 gallon bag.

I like to put down a layer of coir, then 2-3 cuttings lengthwise. Then repeat this pattern to make a cutting/coir "lasagna" until I fill the bag.
Place your freezer bag of cuttings into a black plastic bag (which prevents light from seeing the cuttings, the cuttings root better in the dark). And place the black plastic bag somewhere warm but not hot (~75-85 F). On top of the outside of your refrigerator is a perfect spot.

Freezer bag goes into the black plastic bag and then on top of the fridge
Every 2-3 days open the cutting bag, gently remove the contents, and then repack the bag. This introduces fresh air to the coir and suppresses mold growth.

Essentially you take out the contents (very gently, as to not break any roots). Then using the same coir, repack the bag in the "lasagna" fashion as described above. The idea here is to just introduce an air exchange in the bag, which keeps the mix aerated.

Stale air will become a haven for mold growth, and if you left the cuttings for a month without exchanging the air, you will most likely end up with a bag full of moldy cuttings.
After 1-2 weeks you will see root initials form, which look like white bumps on the surface of the cutting

Root initials on MBVS cuttings
After 2-4 weeks you will see roots form.

New roots on MBVS cuttings

New roots on China Honey / Nixon Peace cuttings
As soon as roots begin to form, you want to plant the cutting. The roots should be no longer than ¼”. If they get longer, you will lose most of the roots when you plant the cutting and the cutting will have less energy to push new roots and open buds. When you plant the cutting be very careful, the new roots are very fragile and brittle.

Think of the cutting as a plant "battery". It has stored energy in it, but without an established root system and leaf system it has no way to replenish that energy. It is using that stored energy to create these systems. And if you break the roots while handling / planting you are wasting its limited energy on re-growing those roots.

If you are planting in a pot, use a loose mixture. Coco coir + coarse perlite is a very good combination which holds moisture but allows for drainage. I personally like to add a little homemade compost in my mix because it gets the roots in contact early with the beneficial soil life that will help it to become a healthy tree.

MBVS cuttings in grow pouches sent out as part of The Year of the Fig project.
Notice the healthy root systems forming clearly visible through the bag
Once roots form and the cutting is planted it will need bright indirect light. This will signal the buds to open and leaf out.

Combination of leafed out and pre-leafing cuttings in my "nursery" area, spring 2016

Close-up of leafed out cuttings.
These were potted and put outside to leaf out in March 2016

Note about cutting sizes:

I have found that 1/4"-1/2" diameter x 4-6" long cuttings with 3+ buds is an ideal specimen. This will typically be hardened growth from last year (<1 year old). These types of cutting typically put out root initials in 1-2 weeks, roots in 2-4 weeks, leafing out in 4-6 weeks and will put on 6"-18" growth their first year (assuming very healthy cuttings that are rooted in the spring).

Larger diameter (>1 year old) cuttings, which can be 1+" in diameter, seem to take longer to form root initials, longer to form roots, longer to leaf out and will do also have a lower success rate than cuttings as described above. But if they do root successfully, I find that they then to push with more vigor and tend to be more vigorous overall. So in essence the trade off is between success rate and tree vigor with larger cuttings.

Now, all that said, if you get small cuttings: root them. If you get large cuttings: root them. Whatever you have, just give it a shot. And don't be afraid to experiment!