Ive moved to canopy fittings and  1 3/8 pipe primarily on cold frames. The Canopy fittings for high roof pitch can be used over and over each winter. This design will shed water, snow off the roof during winter and is strong. The tree pictured is a blood orange tree over 10 feet tall. Easy to attatch poly to with pvc snap clamps. One side of the rood is designed to roll open during warmer weather to allow heat to escape. Thid way the enclose stays covered the entire season except for the roof section. Reduces cover uncover time drastically.  This design can be enlarged to cover full size trees.

The trick to this for me is to oversize the frame so I can get 2-3 seasons each time. I burned myself out a few years ago trying to redo all the cold frames each Sept/October-

Here are the ones that do well for me in 8b/9a

Citrus
Satsuma Mandarin, Xie shan, Owari, myers lemon, cara cara, dekopon (protected), navel, HAMLIN prolific, blood (moro)

Red lady papaya, barbadoes cherry- protected

Olives- mission, arbequina

plums- catalina, santa rosa, methley, burbank

berries- arapahoe and navajo- navajo the sweetest

blue berries- vernon, titan and sunshine blue-which is dwarf and ph tolerant

pears- floridahome, warren and kieffer

Morenga has been prolific here-

Bananas- orianco, viente cohol, cali gold all producing if pup kept inside in pot over winter and planted in spring...

Growing mission and arbequina here. Outside unprotected. No issues disease wise, though recommend planting on a mound or higher area as ive lost both mission and arbequina  to damp soil conditions. Definitley do not do well in low wet areas.  My largest arbequina is now  6x6 but yet to produce. 3 years old now..

Great job on your cold frame!   

On the tag of the plant wrapped around the trunk usually will give you the soil drench date. The fact that there are as many droppings suggest that the initial drench from the store was...non existant  or expired...as it would have killed they nymphs once they began feeding imo.

The denser the dekopon becomes it seems more new offshoots appear from the main . Ive removed these offshoots to keep growth focused on major limbs. Doing so also has eliminated leaf fungus..looks like greasy spo... for me  as the tree gets more airflow/sun. Had the same issue with peaches..

Ive gone through a similar situation with a persian lime. Transplanted into 5 1 1 mix and saw a rather rapid decline in the health of the pant.  I repotted again after finding a fast draining soil,  referenced by Millet some time back - miracle grow - after reading about it on an earlier thread here. The result was immediate. Within a month the plant -which had no leaves at all- flushed out and now itis  in better health than ever. When I retransplanted it was obvious the soil was soggy about 3-4 inches below the surface.

Transplant shock can also cause this as it has for me with a dekopon that is now finally growing.

Finally there is a possibility that transplanting in the winter threw the plant off as all its energy went into preflower development  as its root system was established and now is trying to abort due to shock and is experiencing nutrient deficiency/ leaf loss as a result.

Weed wack flush to ground. Get some thick professional landscape fabric- not the stuff you buy at the big box stores. I use this:
Dewitt P5 5 x 250 Pro-5 Weed-Barrier Landscape Fabric

Stake it to the ground leaving a few inches room around the trunk. ..I use these:
Weed Barrier Fabric 6-Inch Garden Landscape Staples Stakes Pins

It lasts me 4 years exposed to the sun..  and nothing will grow around your trees. Everything else is a waste of time except for  .. round up... which has worked for me as well but needs to be reapplied often. Never killed any of my citrus - I like the one and done method myself.

I usually eat them when they are orange/yellow and no longer green... I dont grow them but do pick them off a tree here along the sidewalk. Id say when they turn color there good.

shiranui has become a favorite in mine.

here citrus canker was discovered in 2014, strain not known at the time but infected all citrus. It was then that I focused on an effective program on my citrus to protect  against this threat.  The canker was found 15 miles or so from my area.  I developed CCSD (citrus canker stress disorder)
here is what Ive been doing. Of course there a side effects but overall it has worked.

Protection methods Ive employed  for canker (and greening)
-Built a 28x14 greenhouse over the ones I wanted to make sure I saved in event of spread into my citrus. The greenhouse has roll up sides with insect netting to prevent the little white moths (citrus leaf miner adults) from entering this area. 

Those not protected totaling 25, I have the followed protocol followed religiously-(this is not a recommendation- it s what i do and is a product of my understanding of the listed chemicals- use your own due dilligence.)

-No pruning, grafting period during months March-December
-No weed eating around any tree base.
-Other than rain and foliar applications keep any and all excess moisture away from the plant - in particular the leaves.
-Copper sprays 3/4 times a year to protect against leaf leasions allowing the bacteria to enter. I used to do this once only in the spring...not anymore
- Soil drench with  Imidicloprid 24 percent every month april    through   /nov after  bloom
-Every flush after bloom I foliar spray  with miticide or  Imidicloprid  as new growth easily outgrows systemic protection and is first attacked
-Contact insecticide sprayed on the leaves every 2-3 weeks.

Im looking now for the longest residual kick back topical insecticide formulation as Malathion,sevin and all those tend to be washed off and ineffective after 5-7 days. Until then  I use Malathion . This is the first defense. Could use any advice or recommendations here....

side effects- explosive mite problems.
(correction for this is easier than the canker though)

mrtexas - you are correct . gmos will be the only solution barring  the development of an injectible/foliar applied/root uptake  systemic targeted bactericide

 






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1.  My site gets plenty of sun in the summer but this time of year it gets filtered/partial light from 8:30-9:30, full sun from 9:30-1:30 and then shady from then on.  Is that enough sun for tropicals or citrus in the winter?  Are some plants better able to handle it than others?

Will need sup lighting. Everything will survive without but will do better with more light.

2.  I'm hoping for 60F minimum at night but that could be unreasonable.  Which of these fruits can handle 50, 40, 30 etc for routine minimum temps?  And which can handle 50, 40, 30 etc for "once a winter" cold snaps?
All my plants which is most of all you listed do just fine with temps down to 40. Id set your temp range 45-50. I keep mine at 40 and have had no prob. 60 will be a lot more expensive.

3.  Are any of these species incompatible with the others?  IE it's easy to grow all except for X because it needs much wetter/drier/hotter/colder/etc.

If in pots you control the irrigation. Most plants will figure out there is less light and heat units and will slow or stop growing during this period. Id seperate what you want to grow into sections as mentioned. Providing for each set of plants as required. It is too extensive to list all the requirements for each type of plant. Id keep it simple and put your most cold tolerant species together in the coolest part of your greenhouse and the plants requiring more heat closer to heat sources weather barrels, heaters, inground heating and so on.  For me  the ability to control the main variables -temp, light,  irrigation are the most important. Once you have these three things accounted for ...the plants will be happy regardless of species as Id say most all are compatible with each other. Im sure there are exceptions but this is the general rule. So... design a greenhouse that can hold say 50 degrees, have the ability with supplemental lighting to provide 8 plus hours of light, be able to provide water and you can grow anything you want. Sounds simple and it is...getting to that point is not so easy. Brian I believe has an excellent thread on this exact topic.
Welcome to the forum! There are many here with greenhouses. Many with much more experience and tips than I. Ive found we all like to share what we can to help.