The color change of oranges in the fall does not occur until minimum night temperatures drop below 55F (13C), further the rate of change from green to orange is related to the severity of temperature lowering and the continued occurrence of temperatures below 55F. At daytime air temperatures of 68F (20C), nighttime air of 45F (7C), and 54F (12C) for soil, bright orange colored fruits are produced. A higher level for any of the temperature variables will produce fruit with less orange color.

Note: If you are trying to win the best of show award at next year's Citrus Expo, follow the above temperatures. (Walton B Sinclair UCR)

Millet, on one of my potted Owari Satsumas i noticed yesterday the one and only satsuma has changed to orange. Should I wait till spring before tasting...to allow more sugars to be present? as you know, my potted plants are in my garage 40 - 45f.

Greg

Greg, one of the things I noticed with the owari satsumas I got from my sister was that at the last time I picked (late Dec), the peel had puffed up and were literally separated from the segments. They were much sweeter than the ones I picked right after Thanksgiving eventhough those were completely colored (that batch was just over the sweet/tart line). The ones I picked in early Nov. were definitely tart--the peels were still somewhat green.

Many times Satsuma's can be ripe even while the peel is still green. This happens often in Florida and other warm states. A lot depends on the temperatures the tree is growing in. Young Satsuma trees normally do not produce fruit of good taste quality until the tree is six or seven years of age. My guess is that your fruit will never get very sweet. I don't know about the solids/acid ratio in Vancouver BC but if your satsuma is fully orange it could be as good tasting as it is going to get, especially when grown on a satsuma tree as young as one or two years old. You can wait a while if you wish, but if you wait until spring I don't think the fruit will still be hanging on the tree. - Millet

I thru two large wheelbarrows of puffy satsumas in the garbage this year from my three 5 or 6 year old trees that are upwards of 8-10 feet tall. I am still buying my fruit from a guy with trees planted in 1990, 1989 being our last citrus killing freeze. I had much better fruit quality on 4 year old fairchild and clementine mandarins, although not 100% as good as they will get. Kishu mandarins from 4 year old tree was fair, those the grackels left me. Fruit quality on golden grapefruit, ujukitsu sweet lemon, and changshou kumquat was excellent. Indio mandarinquat fruit was excellent but extremely sour(I grow these in pots to put by my front door covered with fruit at Christmas time.)

My understanding is that heat is necessary to create the flavor (acid content) although too much heat in late summer can destroy some of the acid-- and cool weather is necessary to create the sweetness. Is that not correct?

Well, I decided to try the owari today as the peel had got a bit puffy and I didn't think the fruit would last. I would rate the fruit as fair + . This is on one of my 4' tall container citrus. I will pay closer attention next year and get to it sooner

Greg

Greg, Your trees should get better with age, but how would you say the fruit was in regards to sweetness and flavor (acid content).

The bland flavor is probably due to the lack of heat. The flavor or tartness comes from acid development which does require heat. Your tree should still get better with age, and that may help with the juice content as well.

Satsuma's, in fact mandarins in general, have several disadvantages in comparison with oranges or grapefruit. If they are left on the tree after becoming mature, the segments dry out which causes shrinkage. With shrinkage of the segments, the space between flesh and peel increases, causing puffiness. (Citrus Growing In Florida). - Millet

Based on my observations of some of my mandarins, like Yosemite Gold, the rinds grew bigger, sometimes as big as grapefruits, the segments inside remained juicy but the same size as the others which did not grew bigger. The apparent growth in volume is just the air space between the rind and the segments.

Some of the mandarins would become granulated though, or will have dry portions on the flesh plus the puffiness, observed in my Owari Satsumas.

About my Lisbon lemons, if I leave them very long on the tree, indeed they become very big also, sometimes as big as ponderosa, but the amount of juice seem to shrink, as only the peels get thicker and thicker and converting some of the juicy flesh into peels. All the growth are just getting the peels thicker.

My experience with my sister's satsumas was the same as yours Joe. The last satsumas (picked in late Dec) were still about the same size internally and juicy, but the peels were puffy and much looser than the ones picked in early Dec.

My lemons are getting bigger, but I have not seen a decrease in juice yet (may happen later). Some of my kumquats seem to almost double in size about the same time they color, but all have been juicy so far. I still have many that are green.

I doubt that the pulp has stopped growing, and only the peel keeps growing. What I expect has happened is exactly what is printed in the book "Citrus Growing In Florida". The fruit was left on the tree past maturity, and the puffiness was caused due to shrinkage of the pulp. BTW the book "Citrus Growing In Florida" is the text book that is used at Florida Southern College to teach Dr. Manners students. I purchased the book from the school's book store. If one thinks that puffiness is due because the pulp stopped growing at some point, but the peel kept growing, I suggest a visit with Larry Jackson and Frederick Davies, the book's authors, or the teachers at Florida Southern College. - Millet

In my case I do believe the pulp suffered from shrinkage. as the outside diameter of the peel didn't noticeably change. (and I thought the shrinkage was from being in my cool garage )

G.