The Illustrated Plant Nut: Grafting the delicious sounding 6-15-150

The beautiful and prolific Kaffir lime

I planted a Kaffir lime about 10 years ago and it has provided me with more than enough yummy lime leaves and some pretty awful tasting lime fruits. Kaffir lime marmalade, no thanks!

When a shoot started growing from the rootstock I decided to let it go so I could try citrus budding. As with many things, time went by. And when I got around to this project, the shoot was taller than our 7-foot fence with perhaps another thorny seven feet heading off into the neighbor's yard.

So I finally got serious about grafting.

What about Huanglongbing?

Huanglongbing ("citrus greening") has devastated Florida's citrus industry and is now in California in Southern California. San Jose and Daly City are quarantined. While I was looking for information about citrus greening in San Jose I found the Fruitmentor's blog (Dan Willey) on Asian Citrus Psyllids.

When to graft?

I read in several places that you need to attempt citrus budding in spring and fall. We were at the end of summer and it was really hot, so I looked around for some help online. I found youtube videos from all over the world - Australia, Texas, and Middle-East. The FruitMentor video turned out to be just right, because he is in San Jose with a similar climate to mine. I emailed him about the correct timing and he said that it should be fine to graft even during the summer. You need to be careful and cover the grafts. He thought that the grafts do better with more heat so summer may be better than early spring.

Which citrus?

I also asked Dan what his favorite citrus are and he mentioned that there are too many, but some are "Oroblanco, Cocktail Grapefruit, and Gold Nugget mandarin. They all hold well on the tree and get ripe even in our cooler climate". His blog mentioned citrus tastings. After reading those I ordered the 6-15-150 mandarin and the Okitsu Wase Setsuma.

After a recent talk on citrus I have added these to the list:

'Trovita'
'Moro' blood orange
'Owari' Satsuma
Ojai Pixie
D'Ancy tangerine
'Fremont' mandarin
Seedless 'Kichu'
'Kinnow'
Meyer lemon
Eureka lemon
Bearss lime
Rangpur lime
calamondin
Australian finger lime

Grafting onto rootstock

What I wanted to do was to cut the rootstock shoot about 4 feet from the ground. The graft would start here, because the tree is on the shady side of a fence. This way the new branches would have a head start to get to sunlight. Good thing I have a tall ladder for picking.

The shoot is about 1.5-2.0 inches in diameter and so I couldn't do bud grafting. So I used the UC suggestion on bark grafting.

from publication "Budding and Grafting Citrus and Avocados in the Home Garden"

I ordered my buds late July and got them the next week. Left them in the fridge for a week, then grafted around August 12. I noticed budding around September 9.

References

Fruitmentor grafting video #2 talks about temperatures for grafting (around the 7 minute mark):

https://www.youtube.com/watch?v=l1HSOy-3JGU
The California Backyard Orchard, Citrus, "Budding and Grafting Citrus and Avocados in the Home Garden"
UC-IPM How to Manage Pests, Citrus
The Citrus Clonal Protection Program (CCPP) budwood cut dates.
CCPP is a cooperative program with the:

University of California, Riverside (UCR)-Department of Plant Pathology and Microbiology
California Department of Food and Agriculture (CDFA)
United States Department of Agriculture Animal and Plant Health Inspection Service (USDA-APHIS)
California Citrus Nursery Board (CCNB)
Citrus Research Board (CRB)
National Clean Plant Network (NCPN) for specialty crops.