I have been advised that the Navelina navel is as cold hardy as satsumas. So, it has sparked some curiosity and I would like to hear from anyone who has experience with this cultivar, especially over wintering in zone 8 areas.
Thanks, Greg

Greg, unfortunately the cold hardy reference that I come across is in other language. Here's a quick info:

http://citrus.forumup.org/post-4445-citrus.html

http://www.eylescitrus.com.au/variety.htm
Navelina (NEW): a small to medium sized tree. Earliest maturing navel (April), slightly oval shaped with a thin, deep orange rind, medium to large fruit, good flavour.

http://aggie-horticulture.tamu.edu/syllabi/422/pdf/class1.pdf
‘Navelina’ sport of ‘Washington’ at Riverside, CA - 1910
Early season, smaller tree, and holds well on tree.

Joe, on the one site, it says the navelina is harvested in April (in Australia) which correlates to a October harvest in the citrus belt of North America.
Interesting....Much like the satsuma.
Greg

Hello,
Navelina is a favorite Navel selection here in Europe. It's very seldom grown outside, because it is better adaptet so mediterran climatics, than so subtropical climatics.
The fruit tend to be smaller than normal navels and often the secondary fruit isn't visible to nearly completly absend.
The smaller fruit gave the cultivar it's name: Navelina means little Navel

Even the fruit is selected for is better cold hardiness, required to be successfuly grown in the mediterran environment, it will not mean, that those fruit is hardy as satsuma.
Many trees died in the last years due freezes, where in other places Satsumas had survived or had only little damage.
Usually most Navelina trees can tolerate more cold than Washington, that's true, but by freezes affected fruit get as quick damaged as in Washington, but trees timb and twigs can widstand better cold, than Washington, but less than Satsuma.

And harvesting times do not realy tell anything about cold tolerance....
So please be carefull, but enjoy this variety, as it stays smaller, bears very good crops of finest fruits and not that large balloons of Washington. They were best eaten fresh and the small fruits made it possible to eat it whole, and sure: The smaller tree also makes a good choice for container culture.
But, please, do not consider this tree as real hardy one....

For me, among the most important qualities that I always look for in citruses is that if they keep well on the tree. Usually good keepers tend to be better tasting and sweeter. They also help free up your fridge. The tree is the best place to store the fruits, unless you have squirrels, tree rats, thieves... Navelina keeps well on the tree.

So far, the navelina grafts perform lousily, are slow growers on all of these stocks that I have tried: Washington Navel, Meyer Lemon, Lisbon Lemon, Sweet Orange, Valencias.

But it should be good as a dwarf tree with smaller canopy good or tight spaces.

Joe, are navelinas available in any retail specialty nurseries in your area?

Steve, thanks for the info on the navelina in Europe. Do you find they need the heat to ripen? Some varieties require less heat units which make them better house plants - like Lemons, limes, calamondins and trovita navels .

Thanks, Greg

There must be some navelina in various citrus nurseries as the Nursery that Millet forever doesn't or will ever like, have produced many navelina grafted liners about a year ago. TreeSource would sometimes sell their stuff to other popular citrus nursery when they come up short, also have sold them to specialty nurseries, and I know now for a fact because of their labeling, eerily familiar font size, combo, ink patterns, plastic sizes, tall tale signs of coming from one company and rootstock combo, and I can see these plant in the Rizzi class nurseries over here, only the pots are different, but they came from Treesource. So far I haven't seen Navelina cultivar itself, only the others which are in excess, perhaps next spring when these have grown bigger for sale in 5 gallon pots. Also those Navelina liners produced by TreeSource could have been ordered by the commercial citrus growers themselves since there are notihing left in the excess inventory that are made available to hobbyists like us.

Navelina is available in the screenhouse budwood program of UCR CCPP.

Only certain parts of Southern California can we find the best tasting citruses. high heat during the summer do not guarantee good flavored fruits especially if you have very cool nights that go along with it too. The diurnal fluctuation that included cool chilly nights will impart acidity on the fruits even if you have high daytime temperature. While this is the perfect recipe for developing the pigmentation within blood oranges, it is not necessarily good for most of my other citruses. The excessive heat that we get during the summer do not translate into good flavor, and the excessive heat only means the plant is almost doing nothing, just merely surviving the heat stress at those times, as the photosynthesis and sugar production would be at a stand still. It is the prolonged moderate heat level that would still have active photosynthesis that helps develop the best flavors. The total number of hours of moderate heat. Excessive heat that we get in the inland valley of California does not count towards the accumulation for good flavors.

The imperial valley are perfect places in California where they have prolonged season of moderate heat. Us here in Northern California, our extreme summer heat doesn't count, plus the fact that our winters are longer than those in the south means that we have a lot shorter accumulation of moderate heat. So our oranges and grapefruits here are lousy tasting, but our mandarins, blood oranges, lemons, limes from our yard are better tasting than those found in the stores, but not at par with those in Southern California.

Joe, could you clarify (define) what you mean by moderate and extreme heat?
I am making the assumption that higher than 35c is extreme and 25c to 35c would be moderate?
Cool chilly nights you refer to would be defined as what temperatures?
What are the ideal temperature range (growing conditions) for lets say, navels? More specifically these navelinas?
Thanks Greg