The Tropical Fruit Forum

I'm doing something similar to your experiment with feijoas. Since they are already hardy down to 5f before getting damaged, I am covering with frost cloth and incandescent lights on a thermocube.

In addition to what everyone is suggesting with temp controls you can graft a piece of your already mature ponderosa to trifoliata which will keep it smaller and easier to cover and thus less space to heat as well as avoid root issues stemming from cold and wet weather.

Ah yes I remember seeing that, looks good. I might have to graft a piece to my tai-tri which is very hardy and vigorous for me here. Should help it grow faster than standard poncirus.

does it retain the "yuzu" flavor and or scent in the peel or juice?

I've only had fruit from it once, but it was OK. Small lemonish sour fruit, a bit smaller than my citrangequat. It also never gets sweet. An extremely thorny plant...

Good to hear that they can take multiple days below freezing in the single digits. Did they flower and fruit after that 9f winter? 

We have 3 fiejoas in the ground that endured 9°F for close to 4 days with steady 15 or so mph wind most of the time. No damage. They are tough. D

not to hijack this thread but which ground cherries are good in zone 7a, are they perennial? i've grown a large annual one that when ripe were OK one year, pineapple flavor, but then got infested with potato beatle or some similar bug the next year. do the zone 7 ground cherries come back from the root system in the spring?

Update: Fruit is mature.



I went to check the fruit today Nov 19th, gave each of them a gentle shake and they popped off cleanly! Would have dropped on their own probably in a couple of days. There were a couple even smaller ones that would not come off the tree so those will not mature in time. Because of the upcoming deep freeze I didn't want to risk damaged fruit if the protection was not sufficient.  I cut open one of the mature ones while still hard, there was clear jelly inside and fully developed seeds, flavor was slightly sweet but mostly sour. I ate the skin too and enjoyed it. At this stage it reminded me of an unripe/hard tropical guava (green skin white fleshed variety) but with better flavor.




I believe I have two different varieties based on the texture of the fruit the 2nd row from the other bush shows more pebbled skin. I did cross and self pollinate but forgot to label which ones were crossed I assume bigger ones are crossed.




I will leave these on the counter until they get soft and post a picture of the interior.

The covered feijoas with fruit did not freeze this morning everything else not covered like the leaves on fig trees are frosted and damaged.


This is just heating from the lights on at 35f/1.66c off at 45f/7.22c:



outside temp:


inside temp:


So the fabric does provide a good amount of frost protection with heating. I might be able to leave the fruit past the date I planned. We'll see.
I hope my lazy experimenting is helpful to anyone thinking about zone pushing feijoas esp if the fruit does not ripen sooner like on my trees

Vnomonee, i am curious what happened to your feijoas that were planted next to the house? Any news on those, couldnt find an update on them in your tread.

The ones by the shed grew back new leaves after dropping everything but didn't flower, those were smaller than my potted plants so still can't say if they will flower after taking that much cold. I'll take a picture tomorrow

Nothing ripe yet. I carefully planted them in the ground,  they were very root bound despite being up potted in the spring. I have no room for such a big evergreen plant in my grow tent this year. If nothing is ripe by Nov 17th I will have to cover them and heat with incandescent Christmas lights, night temps will start dropping below 30f read somewhere the fruit freezes at 28f and will be damaged. Since this variety is not named I'm not sure if the fruit is just late ripening or if being root bound and water starved slowed the growth of the fruit vs in the ground. 

crappy screenshot of a video I took

Not yet, have not been frosted either. Hoping they ripen this coming week there will be warm weather.

A picture of one the fruits last week, its actually gotten a little bigger since then. Between both potted plants I have a total of 15 fruit. If you look up "raregrowsNJ" on youtube I have a video showing how the fruit and the plants look right now.




same fruit, swelling up now:

thanks, I think I'm going to add a few more bricks and then put some frost cloth over the whole thing. Some light will still get through the frost cloth

Very nice fruit. How long do these take to ripen, are they from spring flowers?

I grow edulis in 3 gallon pots, after fruiting I cut them back my oldest plant is 3 years old, very root bound, will need an up-pot or I can just get rid of it and grow a new plant via cutting which I did already. I grow them with a tomato cage so I can wrap the vines around when it's time to bring the plants in. I also grew a banana passion fruit for 3 years but that one never flowered. I pruned it too hard this year and it died to the base but has since resprouted. Maypop is in the ground and comes back every year. Fruit is ok, I defintely like edulis better.