While we don’t have as much of the hardiness problems in Zone 8b, we have big problems with fruit ripening due to our northern latitude.
I am growing a variety of persimmon trees but now that I’ve had the chance to sample a few from my tree and my neighbor’s tree, I am getting discouraged from growing it here.
Background: I picked up 1 Saijo, 1 Nikita’s gift and 1 Jiro earlier this season. Towards the end of the season, I wanted to try out Rojo Brillante, so I purchased that from JF&E.
Only Jiro produced fruits this year. They barely turned color and I brought them in a few days ago. They have softened nicely but the flavor is just blah. Really bland. The store bought persimmons are MUCH better.
My neighbor’s Izu developed much more color, much sooner. It is also much sweeter. I hear it is an early variety.
It seems to me that Jiro is marginal here in Seattle and won’t ripen adequately in a normal year and hence must not be grown. They should definitely not be sold in garden centers as they are every year.
About the other varieties, it seems that Saijo is early and might have a good chance here. Daniel is growing Nikita’s Gift successfully in South west WA but it is a bit warmer there.
Can anyone comment on Rojo Brillante? Is it a variety that needs more heat units than what my area will provide?
Do astringent varieties need more heat than non astringents or vice versa?
He has demonstrated that Jiro’s performance is poor in his climate and thus, it should not be an understock. I’ve no idea what might be a better choice but the staff at ANR Davis might be able to help.
Richard, I am pretty sure you misunderstood my question.
Jiro grows very well in my climate as do all persimmons. We have mature asian persimmon trees that are over 50 years old and 30 feet tall in certain parts of town (International District)
My Jiro also set a lot of fruit this year for a small tree. The problem is ripening the fruit. None of the fruits fully turned color. This problem might be unique to our part of the country where we have mild winters (Zone 8B-9A) but extremely cool summers.
I take it there is no problem with using Jiro as a rootstock.
My original question remains: Are there varieties other than Saijo that are reliable here?
What would really help is a table of Growing degree days for different persimmon varieties.
Alternatively can people post the variety of persimmon they are growing, where they live and when it ripened.(exact day of year).
I can look up the amount of heat required in growing degree days for that location and extrapolate to my location to see if it is viable…
I think with Richard is trying to say. The root stock influences ripening, The Izu graft may be afflicted by the same late ripping as the Jiro host. At the same time in the future yet to be found root stock might induce earlier ripening in a jiro scion.
I see no logic in the idea that earlier/later ripening rootstock will induce the same behavior in the scion; rootstock’s effect on ripening time is extremely small if any at all. For example, Citation is known to induce earlier ripening of stone fruit (and not because Citation is early ripening itself, it’s actually mostly fruitless), but only by a few days, and fruit will ripen on different rootstocks (Myro, peach seedling, Krymsk, etc.) at about the same time. Also, you can have a frankentree with different varieties of apples (or plums, or peaches, etc.) ripening on it over many months, according to each variety’s ripening time. I don’t see why persimmons would be any different. The ripening time is determined (for a given climate) by the scion variety for 99%, not by the rootstock.
There may be logic, but no evidence I know of. If you graft a ginger gold on a yellow delicious it will ripen at the same time it would on any other apple variety or rootstock variety (up to a point- more vigorous trees may ripen fruit a bit later). Persimmons aren’t likely to be affected one way or another if my limited experience is accurate that Kakis don’t tend to be very vigorous, regardless the variety. Even with apples, the more vigorous variety probably would only affect ripening by blocking light from a less vigorous graft. Its vigor won’t transfer to the graft. I believe that only roots in the ground can do that.