Overwintering Kiwi Cuttings

It's been busy here (as you might guess from the absence of posts). But I've pretty much brought you up to the present time and laid out all the projects we have going on here. You have the background on how we got to this point, so now you can expect more current happenings and observations in starting a backyard nursery.

Creating new plants from cuttings is a very unnatural process. In the wild, new roots can form on a section of buried stem which is still attached to and fed by the mother plant. This propagation can be done artificially on a small scale with a method called layering. However, I'm attempting to create many new plants by encouraging root formation on sections of severed stems. These poor things have at most one growing season to form roots, produce new shoots and synthesize enough stored energy to supply a flush of new growth the following spring. Nurturing that tiny spark of life is like trying to start a fire by rubbing two sticks together. You must catch a glowing ember in a nest of fine tinder, then fan it until it bursts into flame and starts feeding itself. There's a period of time where it can get snuffed out very easily.

Of the 187 young plants that were green and growing in the fall, only about 40 of them showed any new growth this spring and even a few of those sort of wilted. That was the main reason for the premature "sold out" sign going up on the store website. So that's the bad news which is only slightly discouraging because I'm committed to this project for the long term and welcome the challenge.

So how can I improve the overwintering process and success rate? Well, it starts with developing a stronger new plant the summer before. I'll go into this more in a later post but briefly I should select only the best cuttings and give them optimal conditions to form roots sooner and have a long initial growing season.

The biggest concern over winter was providing the right environment for young, apparently well rooted cuttings in small pots. They need to survive freezing temps and possible drying without become too wet or freezing solid. Apparently I have not yet been able to produce that ideal environment.

I am reading the highly recommended book "So You Want to Start a Nursery" by Tony Avent, and trying to put as much of the relevant advice into practice without over committing to structures or expense. What I know is that plants in pots above ground are subject to the same winter extremes as anything else above ground. However, normally the roots of any plant are in the ground and experience relatively gradual changes in temperature and moisture. The ground even a few inches down is much warmer and humid than the air.


Kiwis are deciduous and will naturally lose their leaves in the fall and go dormant. A mature plant needs significant "chilling hours" but that is not relevant to a tiny plant struggling for mere survival. I'm pretty sure that a new plant would grow continuously through the winter if kept warm, moist and well lit. This would be possible in a temperature controlled green house which I don't have. Last winter I let them go dormant and when an ice storm threatened, I put them all in the crawlspace under my house for the entire winter. The good part of that was they never got frozen, but the bad part is they never got any light or very good air circulation. I'm not sure what growing they normally do over the winter (if any ), but I know mine didn't do anything for several months. That may have hurt them too.

When it got warm and sunny, I took them out and set them on the large outdoor growing table in full spring sunlight where they could be watered as needed. I was prepared to cover them with a frost blanket and place a heater underneath the table in case of killing frost (which never came this year).


After all that, the ones that still had a spark of life in them took off with great vigor as expected. The amount of first flush spring foliage produced was proportional to their size. However, none of them became big enough to be worth full price. What I think is happening now with the few females I have left is that the small amount of foliage is feeding the root system which will in turn enable a second flush of summer growth.

My plan this coming winter is to have a protected growing area on (or in) the ground with perfect drainage (sand) that can be covered in sections for partial shade during the summer and for frost protection in the spring without having to move the plants.


The good news is that I did sell several plants all over the country and even a few locally. I also have all the papers to make KiwiGrower, a bona-fide Live Plant Nursery, complete with a fully functional on-line store.