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Messages - SoCal2warm

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1
Citrus General Discussion / Eutectic Salts
« on: October 16, 2018, 02:48:19 PM »
A well-designed greenhouse can maintain temperatures in the night using just barrels of water as the thermal mass.

You can look at the temperature data for the SunCatcher design greenhouse here:
https://s3.amazonaws.com/sfc-dynamic-content/uploadfiles/212/Terry%20Carroll.pdf

The nighttime temperatures inside tend not to go below about 58 F, even thought the ambient outside temperatures are going down to between 2 to 15 degrees F.
The parts of the greenhouse not facing the angle of the winter sun to collect sunlight are well insulated. Both the inside and outside of the greenhouse is painted white, to reflect maximum light inside, and help avoid heat loss at night on the outside, and prevent overheating in Summer.

Another technology that exists is to use special eutectic salts instead of water as the heat mass. These eutectic salts can store 62 times the amount of heat by weight as water. The salts undergo a phase change from liquid to solid at a particular temperature.

Farmers have long been using barrels of water, often painted black, to warm a greenhouse. Water does an excellent job of storing and releasing heat, but it canít match the capabilities of eutectic salts.

Like using water as a thermal mass, eutectic salts can be used to store the heat generated by light coming through the greenhouse during the daytime and allow it to be stored so that it can be released back at night. Unlike using water over its liquid range, however, the use of eutectic salts involve freezing or phase change to bank heat.

http://smallfarmcanada.ca/2016/chill-out-storing-heat-inside-a-greenhouse-using-salt/

Quote
The salt formulation used inside Carmeniaís greenhouse is capable of storing 62 times the amount of heat by weight as water. In this trial the salt based PCM stored 260 kilojoules of heat per kg of PCM whereas water stores 4.19 kj per kg. In order to realize the 6-8 degree Fahrenheit increase in nighttime temperature gain achieved in the trial, Carmenia Farm would have had to place 33 45-gallon barrels of water inside its 200 square foot greenhouse. This would have been impossible as 33 barrels would not even fit. A major benefit of the salt-based phase change medium PCM was that it presented a minimal intrusion into growing space.

The principles of heat generation and storage in off-grid greenhouses are laid out in easy to understand terms by James McCullagh in The Solar Greenhouse Book.  Written in 1978, McCullagh mentioned the up-and-coming technology of eutectic salts. Now 37 years later, there are only two companies with salt-based energy storage products on the market. I first reached out to one of them, RGEES, in the U.S.,

I purchased the amount of phase change medium (PCM) product with a phase change temperature of 6C (43F) as recommended by the manufacturer.
The beauty of this technology is that different formulations of the salts produce different phase change temperatures, so farmers in colder climates are able to also use the technology, simply with a phase change temperature that is appropriate for the local climate. The manufacturer produces salt based storage products that change phase at a number of different temperatures, as low as -26C.

Of course, water itself has a phase change temperature of 0 C, so barrels of water are very effective at keeping temperatures inside a greenhouse from going much below freezing, since the water will begin to freeze first before the temperature goes down.

Keep in mind though the night temperature inside the greenhouse will still likely be a few degrees lower than the temperature maintained by the phase change medium.


Dr. Maria Telkas, University of Delaware, proved that Glauber's Salt technology was sound and economical some 30 years ago. She had a couple of patents in that regard. She built a home based on same at the U. of Delaware, and it was a nice practical validation. This technology could have a major impact on how we deal with energy.

Thermal storage is a fundamental problem in solar designs and phase change materials make tremendous logical sense when you go through the numbers. For example, stone, brick and the like have about 0.2 cal./gram/deg C heat capacity. The different mixtures of Glauber's salts, for example, have about 50 to 80 cal./gram during the phase change. Water is 1 cal./gram/deg C. So if you cycle brick, for example, through about 5 degree Celsius change, you only have 1 cal./gram. In this case you have an advantage of 50 to 80 times the thermal storage with Glauber's salts as you do with brick.
As described on our web site, I can heat the north side of our home (passively) with these salts. Because of Dr. Telka's patented techniques, the salts cycle indefinitely. I have had mine for about 20 years.

My salt tubes are about 2 1/2 inches in diameter and 36 inches long and are black-heavy PVC -- sealed with caps on the ends. They work well. As you can see on our web site, I have them on the South side so that the winter sun gives them good exposure -- melting them during the day time, so that they will give off 90 degree F heat at night. If you had them in a circulating water bath, that would probably work as well.

The salts that I have melt at 90 degrees F and have a heat capacity of about 80 calories per gram.
As shown by Dr. Telkas, you cannot use straight Glauber's salt. She came up with a patented mixture to make them work properly.
She used borax to act as a seed to keep the salts from super cooling, and she added clay (I believe bentenite) to stabilize the mixture. The deca-hydrate water bond to the sodium sulfate is a week bond, and if it breaks then you loose the heat-of-fusion properties of about 80 calories per gram. The melting point is about 90 degrees F. The salts I have in our home came from England. Some companies in the states tried her idea, but bypassed the patents and they all failed.

We built our home in 1992 with no furnace and it often gets to -20 degrees F here. It did last us through the winter.

http://www.allanstime.com/SolarHome/Eutectic_Salt/

One such phase change salt material is NaCl∑Na2SO4∑10H2O, which has a melting point at 64 F, phase change heat of 286 kJ/kg

That's simply a mix of regular salt and sodium sulfate hydrate (Glaubers salt), in a ratio of 0.18 g of salt to 1g of Glaubers salt.


Greenhouses can get quite hot inside when the sun is out and the skies are clear, even though it may be cold outside, due to what has been termed the "Greenhouse Effect". However, during the night, temperatures are usually only a few degrees above the outside temperature without some sort of thermal mass. (Although being sheltered from the wind may have some additional benefit protecting the plants from wind chill, movement of air carrying away heat at a rapid rate)


 



2
Yeah itíll be a lot. Iím on border 7b-8a so I think it wont survive that long Or at all in my climate.
I would guess they have about a 50 percent chance of surviving if planted out after the plant has reached 3 feet tall.
You might cover with a cold frame to give it a chance to establish its roots the first year.

3
I'm taking on a project going to attempt to breed Helen's Hybrid (seeded) with Blue Java (as the pollen parent).
From my research, I believe moderate fraction of the offspring will be tetraploid, which can then be hybridized again (with seeded normal diploid) resulting in seedless (edible) triploids in the third generation.

The reason the fraction of tetrapoids would be higher is that a majority of the triploids parental cells that undergo meoisis fail to even properly form normal haploid gametes, so the natural percentage of gametes that escape unreduced then becomes much higher relative to the total number of viable seeds.

Alternatively, it possible to just treat the apical shoots with either Colchicine or Oryzalin (right concentration) to double the number of chromosomes (to tetraploid), then breed one more to get an edible triploid that is now seedless.

4
Cold Hardy Citrus / Re: a few pictures from the Pacific Northwest
« on: October 15, 2018, 04:13:02 PM »
Update on Yuzu seedling, outside in ground, October 15



5
Tropical Fruit Discussion / Re: How good does Carambola taste?
« on: October 15, 2018, 01:56:51 AM »
It tastes good but not really good. There's something intriguing and tropical about the flavor that compels one to want to eat more. But at the same time, the flavor is a little watery, slightly insipid, kind of sour and not very sweet. I think most people would agree it's an okay fruit but not a really good one.

The shape of the fruits are very ornamental and decorative though. It's the type of thing that makes a good garnish on a salad.

You are right though, a full ripened fresh one tastes noticeably and substantially better than the typical one found at a supermarket.
Maybe the typical supermarket one is a 6 or 6.5 out of 10, while a fresh fully ripe one is 7.5 , maybe approaching 8.

Fresh has more and better flavor than supermarket one. If you don't feel like the flavor of the supermarket fruit is anything special, that might change if you try a good one.

This is a comment I found left by somebody else:
"A starfruit picked fresh off the tree tastes substantially different than all the ones I have tasted from supermarkets. True, it was kind of bland, a bit watery, sour, and very slightly astringent, but it also had a very compelling tropical-like flavor to it that made me keep eating."

6
Cold Hardy Citrus / Re: a few pictures from the Pacific Northwest
« on: October 15, 2018, 01:47:29 AM »
Here's another keraji seedling, a bit larger, planted in ground, with a plastic cover:

7
Might be similar to citrumelo, I would guess. Citrumelos seem to do well in zone 8. Sometimes they can survive and fruit in zone 7b.

8
Citrus General Discussion / Re: How to germinate Minneola tangelo seeds?
« on: October 15, 2018, 01:21:56 AM »
Carefully peel off the outer coat of the seed
Wrap in damp paper towel
place into sealed sandwich bag
Place somewhere warm that will not get too cold
In about 1 to 2 weeks, sprouts should come out.
Carefully move sprouts into the largest sized plastic cups you can find, with loose soil.
You may wish to cover the top of the cup with plastic wrap to help hold in the humidity.
Keep the soil moist. This may involve sprinkling with water every 2 to 4 days. Make sure cup gets plenty of light.
An enclosure with artificial lighting works best, for example an 8-watt LED bulb about 12 inches above the seedling.
The enclosure helps hold in the humidity so things don't dry out (which they are prone to do in indoor spaces in Winter with the heat on).
I would not recommend a heating pad directly under the seedling unless the cup is covered in plastic wrap, because the warmth will cause faster evaporation and it will dry out.
When the seedling gets 3 inches high, it should be moved to a larger container, because a cup is not going to provide enough room for the root system, and it will be impractical to keep watering it to keep the moisture level just right (too much water will cause root rot, but if the plant absorbs all the water out of the soil and the soil becomes dry, the plant will also not do well).

Minneola tangelos are cold hardier than orange, but are still not going to be able to survive outside during Winter where you live.

9
Cold Hardy Citrus / Re: Citrus in the Pacific Northwest
« on: October 14, 2018, 08:05:46 PM »


I made a measurement ( 3:30 in the afternoon, partial sun at that time), it's about 6 degrees (F) warmer on the inside of the cover than right outside. And the top of the cover is composed of breathable fabric that lets some air through.

10
Citrus General Discussion / Re: Stopped by Stan's today.
« on: October 14, 2018, 05:02:12 AM »
Interestingly, the Winter on the West Coast was unusually mild. Up in the PNW it never got below freezing the whole month of December.

11
Cold Hardy Citrus / Re: Citreae tribe hardiness
« on: October 14, 2018, 01:19:44 AM »
Atalantia glauca, sometimes named "Native Kumquat" or "Desert Lemon" from Australia
Probably not hardy to zone 7 though.

I might quickly mention Acronychia pedunculata here, which has been traditionally used as an ingredient in incense in China and Korea (adds a pleasant warm peppery amber wood and pine smell).

12
Cold Hardy Citrus / Re: Citrus in the Pacific Northwest
« on: October 12, 2018, 05:16:31 PM »
various citrus seedlings inside greenhouse


(some of them are cold hardy, others not, just off the top of my head, some of them include keraji, yuzu, pomelo, oroblanco seedlings, and others)

13
Cold Hardy Citrus / Re: Citrus in the Pacific Northwest
« on: October 12, 2018, 04:53:11 PM »
The Bloomsweet needed a little help to deal with the cooling temperatures



14
Citrus General Discussion / Re: Polyembryonic seeds
« on: October 11, 2018, 03:38:10 AM »
So basically there is no 100% sure way to tell if a seed is true to the parent...

A bit disappointing. :p
This is one of the biggest impediments to breeding.

I would agree that there is no 100% certain way to know (in the absence of genetic analysis), but there are a few strategies that can be used in intentional breeding to be very close to certain (maybe 97% sure). One would be for example if the seedlings display any obvious traits that can easily differentiate them from their seed parent, usually leaf shape.

It's a bit too complicated to get into here, but if you carefully select the varieties, using the right combination, and emasculating the male/female parts of the flowers of the two parents, you can be pretty sure.

And again, with certain citrus varieties you can be pretty sure. Oranges are almost certain to produce all nucellar seeds, while original species citrus like pomelo, citron, many varieties of mandarin, are sure to produce all zygotic seed.
This is very generalized but most of the seeds in lemons and grapefruit will be nucellar, while some will be zygotic.

15
Citrus General Discussion / Re: Polyembryonic seeds
« on: October 11, 2018, 03:24:54 AM »
If a citrus seed is polyembryonic, will it have more than 1 shoots coming out?
Usually, but not always.

By definition, polyembryonic seeds have multiple seedlings sprouting up from the same seed, but usually when the term "polyembryonic" is used it is referring to nucellar seed, meaning the embryo in the seed originated from nucellar tissue and thus did not result from sexual recombination. If it's nucellar, that essentially means it's going to be a genetic clone of its parents, with the same genetic composition.

The seedlings coming out of polyembryonic seeds are usually all nucellar, but in some less common cases one of the seedlings (not uncommonly the weaker one) could be zygotic (meaning that it originated from sexual recombination and was passed down genes coming from the pollen).

Different citrus varieties have different percentage ratios of nucellar to zygotic seed, ranging from all zygotic to virtually all nucellar.


Polyembryony is a good way to spot nucellar seeds, but it's not always completely reliable.

16
Tropical Fruit Discussion / Re: Difficulties with pulasan
« on: October 09, 2018, 05:03:24 PM »
I would suggest keeping them inside a greenhouse, or enclosure with artificial lighting to hold in the humidity. When they are first sprouting, they need humidity and moisture, and are vulnerable to drying out. But pretty soon they can become vulnerable to root rot if there's too much moisture in the soil. It's a narrow range, so it can be difficult. I would suggest using larger containers, that are bigger than how far the roots expand out. More soil volume helps to keep the soil moisture level more constant, so it doesn't dry out or get too wet. For example, a 3-inch high seedling might need a 8-inch wide container. 8-inch high seedling, then 12 foot wide container. Make sure to use good quality soil that's both good at holding moisture but won't hold too much water. Also for young seedlings, don't expose them to full sun. Their small root systems can't handle the water draw from that level of evaporation. Make sure the soil is fairly loose too, so there's air in there for the roots. You know there's too much water if the water has displaced all the air in the soil. Roots need to breathe, as well as moisture.

Pulasan is also the most tropical member of the lychee family, so I would keep the temperatures from going down too low. (maybe above 67 all the time, and usually in the range between 77 to 86 degrees Fahrenheit)

17
Kuganskaya, ripening up more now:



I bought a quince at the regular market and did a comparison between the Crimea and the market quince. It really made me realize how edible these special quinces were by comparison. For the market-bought quince, it was like biting into something very dense, and the first bite was like swallowing sawdust. For the Crimea, it was only a tad bit dry, and that was really more after the second slice. I'm not really sure you'd even notice any astringency if you only had one slice and it was thinly cut. The Crimea, you really have to eat two or three thick-cut slices before it really starts becoming unbearably astringent. The Crimea is absolutely edible in comparison.

I'm going to say the texture/flavor of Crimea leans a little more towards apple, and the texture/flavor of Kuganskaya leans a little more towards pear.

Keep in mind this is in the Pacific Northwest, and most of the ripening period is going into the cool season. I'm sure they'd probably ripen better somewhere much further South.

18
Citrus General Discussion / Re: Great Sour Orange Marmalade
« on: October 06, 2018, 02:49:25 PM »
The original marmalade was made out of Quince, but they then discovered marmalade could be made out of sour orange.

There are several other citrus varieties that marmalade can be made out of also. Calamondin, for example.
In New Zealand there's a local variety called "Poor Man's Grapefruit". The Chinese make a sort of marmalade tea out of citron.

19
Rainy and temperatures in the 80s, the mangosteen is doing good.

20
Tropical Fruit Discussion / Re: Tamarind in CA?
« on: October 04, 2018, 01:16:15 AM »
I'm pretty sure tamarind would grow okay in Southern California. It's fairly drought tolerant.
It might even grow bigger and faster than you want it to grow.

21
Cold Hardy Citrus / Re: a few pictures from the Pacific Northwest
« on: October 03, 2018, 03:55:06 PM »



Yuzu, Pacific Northwest zone 8a

22
Would I say these two are "edible"?
Well, sort of. Maybe on the border between "semi-edible" and "edible", definitely edible in a survival situation.
They're interesting, and quince has kind of an intriguing flavor, and I might feel like snacking on a little bit, but I don't think I'd feel inclined to eat a whole fruit in one sitting. Maybe about a fourth to a third of the fruit makes me feel like I've had enough (although the size is a little bigger than an apple).

23
Crimea fruit





Texture not very much dissimilar to a Granny Smith apple.
Slightly astringent, but better than a bad Hachiya persimmon.

24
Cold Hardy Citrus / Re: Citrus in the Pacific Northwest
« on: October 02, 2018, 01:28:23 PM »



enclosure around Satsuma

25
Kuganskaya




The Crimea fruits on the tree are beginning to develop a more quince-like fragrance now.

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