Tasty fruiting cacti for a public garden

[Rei]

Hi all - I'm new to this site, so go easy on me! I'm helping design the contents multi-climate-zone public greenhouse with a focus on edible plants - and one of the climate zones will be bright/hot/arid. So perfect for cacti I've been working on my research and here's what I've come up with so far - could you offer any feedback on these species (new / useful info, opinions, etc) and suggest new ones where you find it appropriate? Factors that matter are any combination of:

* Fruit quality
* Fruit quantity (relative to how much space the plant takes up)
* Plant/fruit/flower appearance (and in the case of the latter two, how much of the time they're actually visible on the plant for people to see!)
* Nutritional / medicinal properties
* Interesting stories / history / religious significance / etc.
* Difficulty to acquire / cultivate / bring to fruiting, and how long it takes to do so
* Scent, if present (e.g. flower scent, etc)
* Hazard level (in the case of cacti, how badly people who don't read signs / respect barriers would be to injure themselves on the thorns )
* Anything else that seems relevant
* Bonus points for anything that can still fruit productively in shade of other plants!

We have full control over the environment - e.g. soil type, root space, temperature, humidity, even light intensity.

So, without further ado, here's my list so far and my "general details" I've gathered thusfar (without digging too deep into any of them). I'll put my take on the appearance after the name, in the form "fruit/flowers/plant":

* Hylocereus sp. (Dragonfruit) - Útlit: 4/5/3,9
Yellow = more flavourful than red. Red with red flesh is better in taste than red with white flesh. Unfortunately, from an appearance perspective it's reversed. Also, I'm not sure that when people talk about a good yellow dragonfruit that they're talking about yellow Hylocereus, I think they may be talking about Selenocereus.
Fragrant flowers, although I've heard at least one person say that they don't like the smell.

* Cereus repandus (peruvian apple cactus) - 2/5/2,3

* Stenocerus:
* S. queretaroensis or S. stellatus - 4/4,5/1,8
I know one person who's growing one of the above and the fruits have a great appearance; the taste was said to be good.
* S. beneckei f. inermis - 1/3,5/4,2
Striking plant with the contrast between the light colour and blood-red thorns - although I don't know how good the fruit are.
* S. thurberi - 2/4/2,8
Better/sweeter than S. gummosis, although I don't have a good grounding on that comparison.

* Opuntia
* O. ficus-indica ("prickly pear") - 2,5/3,5/2
Nutrition = 3,4/5
Fruit and nopales. Best to put the fruit in a blender, due to the hard seeds. Need to remove the (annoying) fine thorns.
Said to not like humidity. But some varieties are said to tolerate it?
Burbank's Spineless / Burbank's Thornless - Grown specifically for it's fruit
Even good varieties don't have a particularly complex flavour, but their flavour is a sweet "taste explosion".
* O. gomei 'Old Mexico' - 2/3,5/2
Thornless (fruit quality..?)
* O. cacanapa 'Ellisiana' - 2,5/3,5/2,4
Thornless (fruit quality..?)

* Cylindropuntia arbuscula - 2/2/1
Said to be very good, but is the fruit quantity worth the space?

* Mammillaria grahamii (Graham's Nipple Cactus) - 3,7/5/2,5
Taste: "strong strawberry", but even better than strawberry.

* Myrtillocactus geometrizans () - 1/3/5
cv. christatus - Ridiculously cool looking, like a statue
cv. Fukurokuryuzinboku - Like a column of breasts
Fruit like raisins. But it doesn't look to yield a lot of fruit relative to the size?

* Epiphyllum sp. - 4/5/3,8
Said to be way underappreciated, as far as cactus fruit go. Beautiful flowers. Fruit like little dragonfruits.
'Curly sue' monstrose, however, said to give lousy fruit.
Tolerates shade well

* Polaskia chichipe - 1,4/3,5/2,5
Blue berry cactus

* Gymnocalycium saglionis - 3,3/2,9/1,9
Was said to be the favourite of a cactus collector in the Czech Republic. Light-pink fruits.

* Cipocereus minensis - 4/4,5/2
Said to be the best Cipocereus, although that doesn't tell me a lot Striking blue flower stalks and fruits.

* Echinocereus engelmannii (Strawberry Hedgehog) - 1,5/4/1,5
Fruits said to be good, but they sure look to be covered in wicked spines.

* Selenicereus megalanthus (Pitahaya) - 4/5/3,9
"Climbing cactus with yellow fruit" - yellow dragonfruit. I think this might be what people mean when they talk about a particularly good yellow dragonfruit.

* Trichocereus grandiflorus (Torch cactus): - 2,8/5/2,5
Reminiscent of a yellow dragonfruit. Said to become sweeter as the flesh dries (so, not so much when fresh?)

[ElieEstephane]

If you want the best fruit for space, you're gonna have to go with dragon fruit. Columnars don't make as much fruit compared to how much apace they take up.
Opuntia ficus indica is not sensitive to humidity ( if not too cold) and can produce a signficant amount of fruit. I find the fruit to be incredibly delicious.
Harrisia sp are good fruit cacti that are similar to hylocereus.
Corryocactus brevistylus has an interesting sour fruit but i'm not sure you can easily find a plant.
Mammillaria fruits are usually edible and said to taste like strawberries notably mammillaria prolifera and wrightii. (Best for space)
I hear epiphyllum fruits are very bland but i never tried them.
Pilosocereus fruits are good, specially pilosocereus gounellei
Not sure trichocereus fruits are palatable.
Some ferocactus fruits are said to be sweet but not sure which.

My 2 cents

[greenknight]

Mammillaria prolifera is the most abundantly fruiting member of that genus, and the bright red fruits remain on the plant for a very long time. It also offsets freely, soon forming a sizable clump.

[Grimm]

It may also be worth looking into the cacti that have edible stems, such as the Opuntias and Ferocacti (including Glandulicactus uncinatus)

[ElieEstephane]

It may also be worth looking into the cacti that have edible stems, such as the Opuntias and Ferocacti (including Glandulicactus uncinatus)

I always thought it to be heartbreaking to actually cut up a big ferocactus and eat the core

[Grimm]

It may also be worth looking into the cacti that have edible stems, such as the Opuntias and Ferocacti (including Glandulicactus uncinatus)

I always thought it to be heartbreaking to actually cut up a big ferocactus and eat the core

So do I, but people do it. I'm not sure if the OP is aiming to actually eat the fruit as the main purpose of this, or display plants that produce the fruit, in which case having a couple of Ferocacti as an example of what people eat would be fine.
Also, when done commercially, I suppose it's no worse than cutting up a 100yo+ tree for its timber.

The following shows a Glandulicactus being cut up for eating: - http://www.cactusexplorers.org.uk/Cactu ... 20No.1.pdf

[DaveW]

I think they only drink water from cacti in films and in extreme emergency if they have run out water and it's a last resort. However what is commercially sold as cactus water is evidently not that you see in the films when they slice a globular cactus and drink the sap:-

"When you’re lost in the desert, cacti will save you, right? At least, that’s how it works in cowboy movies. Unfortunately, cacti aren’t quite the life preservers they’re made out to be. The prickly pear cactus is one of the only safe ones, but you have to cook it to reduce the acid. Too much water straight from the plant can make you sick. Commercial cactus water is actually made from the fruit of the prickly pear cactus, not the cactus itself."

See:-

https://arizonadailyindependent.com/201 ... -you-sick/

https://www.theactivetimes.com/how-surv ... ter-desert

Basically apart from the fruit you can't usually directly eat any cactus parts without they are cooked first or treated to remove the toxins in some other way. Even eating Lophophora's will make you vomit if you do not use the same preparations the indigenous people do. I believe Neowerdermannia's are also consumed, but don't know if any special preparation is done to them before eating.

[Rei]

Wow, thanks for all of the great posts, all of you! This is all going in the database.

We're mainly interested in things that can be eaten out of hand, in "sample sizes" rather than large portions. Concerning cacti with edible flesh, are there any that are actually decent out-of-hand? The above article from DaveW suggests that there are spineless Opuntias that can be eaten raw, but they make it sound like it's not appetizing ("cattle feed"), so that wouldn't be worth wasting space on (unless its fruits justify it vs. other Opuntias).

So from a productivity-per-unit-space standpoint we have have dragonfruit in a solid lead. I see annual productivity figures for it of 5-30 t/ha, with a high around 50t/ha. I also found figures for Opuntia - cultivars Nudosa and Ofer are around 10t/ha each, but there's also Meyers (20.64 t/ha) and Morado (18.53 t/ha), and in controlled conditions, (unspecified varieties) can yield up to 50 t/ha; 22 is considered "medium to high". Can't find any info about the productivity of thornless cultivars, unfortunately. I can't (unsurprisingly) find yield figures for the other cactus species.

So if we put the above two at 50 t/ha, then perhaps 12t/ha for most of the others, except perhaps 40t/ha for selenicereus and harrisia since they're similar to hylocereus (but less selected in cultivation), and maybe 25t/ha for M. prolifera, and maybe marking some like Myrtillocactus to 7t/ha (based on the unimpressive pictures I've seen of fruiting)? Obviously "precise figures" aren't needed, I'm just looking for a way to compare them with each other.

From a fruit quality standpoint, on a scale of 0 to 5 (including taste, difficulty of eating, how much edible flesh you get out of it, etc - 5 being "knocks it out of the park in every regard"), does this sound good for fruit quality, or do some sound overrated/underrated?

Hylocereus, red-white: 1,5
Hylocereus, red-red: 2,5
Selenicereus, yellow: 3,5
Harrisia sp: 2,5?
Stenocerus: 2,2?
Cereus repandus (peruvian apple cactus): 2,8?
Cylindropuntia arbuscula - 3
Optunia ficus-indica: 3,8
Corryocactus brevistylus: 3,5
Mammillaria sp.: 3
Epiphyllum: 0,7
Pilosocereus gounellei: 3
Ferocactus: 2? Need to research more.
Myrtillocactus: 2?
Polaskia chichipe: 2?
Gymnocalycium saglionis: 3? (found a post on this forum that said it tastes like Cereus fruits, so that's another datapoint...)
Cipocereus minensis - 2?
Echinocereus engelmannii (Strawberry Hedgehog): 2,5?

From a flower scent smell.... 4 out of 5 on the hylocereus/selenicereus/harrisias, little scent from the others? Or are some worth noting from a fragrance perspective?

I'll of course be digging into all of these more on my own, I'm just wanting to get your takes on them before I do Oh, one more thing I should probably ask: I know that at least the normal, non-thornless Opuntias have those little tiny super-annoying thorns. Do any other cacti on the list have any "hazards" that should be mentioned, or can you pretty much judge them from the look of their spines?

Thanks a bunch!

[DaveW]

Regarding safety of the public. One other hazard I can think of if you want people to eat the fruit or any of the plant, be careful using fungicides and insecticide's on them, particularly systemic ones.

The only other is Opuntia's have glochids ("the tiny annoying thorns") as well as spines so are a bit antisocial. Some of the Opuntia's also have sheathed spines which cover spines that are barbed like harpoons and really grab your flesh, ripping it as you try to get them out. The problem of course can be children who just love to touch things.

See:-

https://www.kcet.org/socal-wanderer/how ... rated-body

https://www2.palomar.edu/users/warmstro ... aWash1.htm

[Rei]

It will be under glass, and we thankfully have a local provider of biologic controls, so hopefully we'll never have to resort to pesticides. It's to be integrated into commercial/retail space (a "Biodome" integrating exotic food cultivation with everyday activities), so the value per square meter is rather high compared to a typical garden, and thus plants will be receiving the best care we can give them.

We can always protect the public from more hazardous plants with barriers, but of course that lowers their desirability - hence the ability to assess thorn hazards is important in the selection process. Is anything other than opuntias particularly noteworthy from a thorn perspective (e.g. particularly sharp/annoying, or abnormally inoffensive)? I remember glochids well - while I live in Iceland, I grew up in Texas I once made prickly pear jelly with my grandmother, although I was too young to remember what it tasted like (I remember that it stained, though )

[ElieEstephane]

I think you best bet will be epiphytes (hylocereus, epiphyllum, lepismium...), not sure if harrisia classifies as an epiphyte. I've grown dargon fruit myself and waten commercial ones. While.commercial ones taste like a celery stalk, home grown ones taste very sweet.
As for opuntia ficus indica, there are several spineless varieties but the fruit will always have lots of glochids. Your safest opuntia will be stricta/dillenii which has far less spines and the fruit is almost nude

[Rei]

Thanks. So O. stricta v. dillenii has fewer glochids than Burbank's Thornless, O. cochenillifera and O. cacanapa var ellisiana, etc, and/or a similar level of glochids but better fruiting/quality? Because I've read good things about each of them concerning thorns/glochids (pictures of O,cochenillifera fruiting don't look very impressive, but O. cacanapa seems to put out impressive flushes, as well as attractive flowers and a rather curious look to the pads). It's also my understanding that Opuntias become thornier in drought, so keeping them at the upper end of their acceptable moisture range (which I understand to be 1200mm/yr for O. ficus-indica) would be optimal, correct?

Ed: O. cacanapa fruit is said to be dry and inedible. Okay then.

[ElieEstephane]

To be honest, what i said above about cactus fruits is all i know.
I have opuntia ficus indica lining my olive orchard as a living fence. Both the olives and cacti only receive rainwater. If it was a rainy year i get a good amount of fruits and if it was not, fruit production is reduced.
The hylocereus in my yard produce several pounds every year but i've never really quantified them to judge yield on a commercial scale

[Rei]

That's okay, you've been more than helpful - thanks a lot!

As a side note, I hope things are okay over in your part of the world. I follow what's going on in the conflict across the border daily

[ElieEstephane]

That's okay, you've been more than helpful - thanks a lot!

As a side note, I hope things are okay over in your part of the world. I follow what's going on in the conflict across the border daily

Thanks for your concern but we are actually a peaceful country that is the safest in the region (crime rate significantly less than the US) and the only army that defeated/eradicated ISIS completely. We run a lot of preemptive anti terrorism tactics that are extremely effective. Just yesterday, one of the major ISIS leaders in syria and iraq was arrested. Even in Syria things have settled down greatly although if you hear non local news it will picture it as if hell is raging in Syria. Sorry to disappoint but most of what you hear in the news is either partly or completely false.
Back to the subject at hand, you should try some references from Israel. I hear cactus fruit production is much more commercialized there.