The Tropical Fruit Forum

is mamey different enough from green sapote that it is worth growing both?   I have tried mamey once or twice and really liked it, but right now I have only a grafted green sapote

That is a really impressive fruit set.  Shame it broke the plant, but what a harvest. 

I have tried them.  My greenhouse is very buttoned up so there isn't easy for them to simply fly away.  They unfortunately didn't seem to make a difference.  I did notice there was a new generation of the mealybug destroyers appeared some weeks after I thought they all died off, but they didn't put a dent in the mealybug population.  I have been fighting mealybugs for years and the most effective control for me has been hort oil.  Every winter when my greenhouse is packed full of plants the mealybug population booms, and I try to hose them off as best I can.  In spring when I can bring container plants outside I try my best to eradicate every mealybug and apply hort oil all over.   No pesticides seem to help, even high doses of imidacloprid. 

I know breadfruit trees can get huge, but are they capable of fruiting at a small size?  I never tried because I only like fresh eating fruits, but I wouldn't count it out based on climate alone if you have a greenhouse.  I don't know much about breadfruit specifically but all the other artocarpus have been surprisingly easy to grow (so far)

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When the sun is shining in my greenhouse I never want to leave, and it was the best thing during lockdown.

Yup, that's the thing about efficiency... the most efficient "greenhouse" at your latitude is probably an insulated warehouse with grow lights.  But it won't feel very nice to be in.  Better to spend money on nice environment you like being in even if it isn't very efficient. 

I'm certainly no expert on ultra tropicals, but I think I've read chempedak will fruit at reasonable size.  However, none of the artocarpus I've tried to grow in containers do well, but they all do great once I put them in the ground.  Likely the soil, as the container ones aren't root bound.

I have had a mallika mango in ground for years and it looks great.  It first flowered three years ago but fruitlets never got past pea sized.  Two years ago fruits held on longer/bigger but still not to maturity.  Last zero blooms or fruit set.  It is blooming heavily this year so hopefully I'll get a crop for once.  I have recently read they don't like water while holding fruit and I was always watering it constantly, have sinec stopped that.  The tree itself has been very healthy aside from a minor armored scale infestation and resultant sooty mold.  I'm not exactly sure what anthracnose is but I don't think I have it.   You should be able to grow one. 


I suggest you buy a bunch of small seedlings and see how they do, and if they do well replace them with grafted types.  I found almost everything grows well and the ones that don't are for reasons I can probably correct.  It will never be efficient but it is entertaining. 

I did not realize that the flowers have those sheaths like the leaves do, I will have to go re-check my tree and see if there might already be some!

I'll take a pound, I've always wanted to try these.  SMing you

Ebay will let you return anything, and if they don't your credit card company will

One nice thing about covering the greenhouse at night is you can run grow light without the light escaping (and bothering nearby animals & neighbors).  I live in a fairly dense suburban area so I don't run grow lights, but if I could get a solution to cover the greenhouse glazing at night I would

here's the diagram from that article of the chinese greenhouse design


I had built a model of a design I want to try that is frameless... I am thinking the arch effect of a 8-12mm thick bent plastic glazing panel might be strong enough on its own

Has anyone created a passive solar style greenhouse, requiring little to no extra energy input?
Something using a similar concept to this:
https://www.mainepublic.org/environment-and-outdoors/2023-01-25/this-maine-home-can-stay-70-degrees-without-a-furnace-even-when-its-freezing-outside

These passive solar designs always seem to ignore the common winter condition of "freezing, windy, cloudy, wet for days in a row" where there is no meaningful solar heating and any accumulated thermal mass is gone by the second night. 

I have spent a ton of time thinking about insulation and greenhouse energy efficiency over the years.  The biggest problem is that the insulative value of  even the best glazing is awful when compared to something like a proper insulated wall.  The only solution that makes sense to me is to have some kind of insulating blanket that can cover the greenhouse at night.   Finding something that can do this while surviving the elements, wind, moisture, etc is though.  It seems chinese growers would use thatch and simply roll it up manually twice a day and replace it as needed.  Having something automated and long lasting will be expensive and heavy, something like polyurethane rolls on a spool.

The floor of a greenhouse is a massive heat sink, too, so you have to insulate the foundation perimeter and possibly the floor

If you accept that the insulation will be poor and focus on cheap energy things like geothermal are options.  Or solar-heating a large mass of water and extracting the heat at night. 

At some point if you have zero air exchange it will harm the plants and you'll get mold.  Once you start air exchanging your heating efficiency drops drastically.  Things like heat recovery ventilators exist but more expense and complication there.

I am fortunate enough to have piped natural gas which is dirt cheap.  It costs me around $100 per month to heat my greenhouse in winter.  If I used electric it would probably be triple that, and propane some where in between.