This is a repost of one I made January 9th, and which apparently was lost when Go Daddy rehosted the web site.
This time, I'll save the post so it doesn't get lost again. For some reason the images get stuck at the end of the post, rather than at the desired locations.
The post is about the Changsha tangerine I grew from seed. Originally there were 36 seeds graciously supplied
by Stan McKenzie. 24 of the seeds produced viable offspring, which were placed in one gallon pots in the ground
and left unprotected as 1 year seedlings in 2008 in order to winnow out the less cold hardy plants and ultimately
obtain the hardiest seedling of the 24.
In December of 2008 we had an Arctic event where the temperature briefly rose above freezing only once during a
180 hour period and the nightime low dropped as low as 15F (-9.4C) 20 of the seedlings perished during that
event.
In December of 2009 the remaining four seedlings experienced an Arctic event where the temperature never rose
above freezing for 114 hours and there were four nightime lows between 10F-12F (-12.2C to -11.1C). Only one
seedling survived that event. That seedling was subsequently grafted onto a Flying Dragon rootstock, and both the
original seedling and the graft were placed in the ground. Also placed in the ground was a random Changsha
grafted onto a PT rootstock. Both grafted Changshas were protected until they came of a good size.
In 2013 there were two Arctic events. The first in early December with a low of 10.5F (-11.9C) and 117 consecutive
hours where the temperature never rose above freezing. The second in early February was short, but had temperatures
that ranged between 18F (-7.8C) and 22F (-5.6C) for 36 consecutive hours. The original Changsha on it's own roots
perished that winter because it was not dormant in early December, due to a preceding warm November. The sap froze,
the bark split and it bled to death come spring. The two grafted Changsha were still being protected at that time.
Finally, in January 2017 both now unprotected grafted Changsha experienced an Arctic event where the temperature
stayed below freezing for 316 hours except for a twelve hour break mid freeze when the temperature rose to 35F (1.7C)
During that event there were four nights with low temperatures between 12.5F and 16.1F (-10.8C to 8.8C) and one night
where the low was 8F (-13.3C). The nearby Pearson Airport recorded an official temperature of 6F (-14.4C) that night.
My seed grown Changsha sailed through that even virtually undamaged; In fact, it had less damage than the Yuzu and
Sudachi and only slightly more damage than the Morton Citrange. The random Changsha on PT rootstock completely died
with no grow-back- the PT rootstock itself was undamaged.
It appears that I've successfully selected for a hardier Changsha, with one caveat. As seen in the picture below, my
Changsha is only six feet away from the NW corner of my cottage, and there are two 55 gallon rainbarrels next to it.
While the rainbarrels had frozen solid by the time the 8F night arrived, the combination of house and barrels may have
locally modified the temperature.
The grafted tree had its first large fruit along with half a dozen pithballs in 2019, twelve years after the seedling
sprouted. It's possible that grafting delayed the fruiting by a year or two. This year there were 23 full sized fruit
two of which were shared with board members at different times. The first one was shared in mid-November and was very
juicy with a very good bright spritely tangerine flavor. The peel removed easily and had an aroma reminiscent of
Marijuana (how do I know that?) or, more properly said, some kinds of Marijuana smells like the peel. The second fruit
was shared with SoCal about a month later and is described in his post above. It had lost some of its juice by then.
The remainder of the fruit were harvested in early January, at which point they were quite dry and had lost most of their
flavor and 'zing'. Some of these fruit are shown below with a ruler.
Because they had lost so much juice, it took eleven fruit to obtain the 90 ml of juice needed to measure the Brix level
using a calibrated hygrometer. 15 ml of that juice was then titrated using 0.2N NaOh solution to obtain an acid level.
The results:
Brix=10.7%
Acid=0.8%
Sugar to acid ratio (S/A)=13.37
There were 102 seeds in the eleven fruit, an average of just over 9 seeds per fruit. Some had more, a couple were seedless.
This is a higher S/A level than any of my Satsumas, but then, the acid level is substantially lower than any of my citrus.
I drank the remaining 75 ml of juice. It was quite bland and insipid, likely due to the low acid level. It reminded me
somewhat of the texture and blandness of apricot juice, but with a mild tangerine flavor.
In retrospect, I made a mistake by waiting so long to harvest the fruit. Changsha's, it seems, do not hold well on the tree
unlike my Satsumas and Ichandrins.
Some additional takeaways from this 13 year experiment.
It's possible to grow some Changsha without protection in zone 8a in the American Pacific Northwest, at least in sheltered
areas.
At least in SW Washington and the Williamette valley Changsha ripens early enough for quality fruit. This actually surprised
me. I knew that Changsha's were earlier than Owari, but I didn't expect them to be that much earlier. Owari does not reach full size or maturity in the PNW
While I think my Changsha is hardier than average, the proximity to my cottage cast uncertainty on that. Therefore, this
year I plan to graft it onto my two available rootstocks, then put them out in more exposed location; Protecting them until
They become large enough to withstand Arctic events- two or three years of protection typically. If they survive, this will
confirm my suspicion.
In response to a comment made the first time I posted this- a comment also deleted by Go Daddy- I do indeed plan to plant the
seeds I get from this years crop, then perform a mass selection to attempt to obtain an even hardier Changsha. Horrible
things will be done with a freezer in a first cull, rather than waiting for an Arctic blast. I'm brutal-you betcha I am.
I was surprised how low the seed count was. I remember reading that Changshas more typically have 20-30 seeds per fruit. It's
possible that it's the plant, but actually I think it was a pollination issue. This year was rather cold and wet during bloom
time, which probably hindered the bees. Several other of my citrus also had lower than usual seed counts. In fact, it may be
that the copius number of sugar ants that suck the nectar may play a minor role in pollination, This raises an interesting
possibility which I may explore this coming summer.
Finally next season I plan to start sampling the fruit when the peels just start to turn color. This usually happens with the
advent of cool nights around mid-October here in Vancouver WA., though that varies from year to year. Hopefully this will
aid in determining when to harvest for best flavor.