The Tropical Fruit Forum

Somebody mentioned in another thread that abiu may be sensitive to root disturbance.  I guess I am testing that theory, as I just subjected my container abiu to the usual 20gal root-pruning.  Previously I was up-potting it and not root pruning, but this is as large of a container as I am willing to go so this is its future long term. 

I pulled it out of the pot, cut off a few inches of the root ball all around with a saw, including all the circling roots hugging the edge.  Added soil to fill the gap and put it back.  Little to no top pruning this year as it isn't too tall or wide yet. 

Time will tell if it does okay or not... I'll report back how it goes.   

before root pruning:


soil & roots removed:


current state:

This should put out a flower pretty soon, right?  And do I cut off all the pups except one?   

It is in a 20gal container, and is about 10ft tall

My ilama scion seems to have a bacterial or fungal disease causing warty spots on the leaves.  Any idea what this might be and how to treat it?  I would hate to lose this scion and successful graft.  The rootstock trees (cherimoya) have no symptoms, nor any of my other annonas. 

I got a mamey fruit today and one of the seeds looks like it has a growth, I can't tell if this is just a part of the fruit or if this is growth from the seed.  It seems to be spilling out around the hard seed coat which mostly fell away.

We all spend a lot of time thinking about soil mixes and drainage.  I have personally seen severe tree damage or death caused by large dry areas of hydrophobic soil inside of a container mostly caused by too much peat moss.  But whenever I buy some decorative plant or use seed starting soil I am always amazed to see mostly-peat soil draining like sand.  I now know this is because they have added wetting agents.  It makes me wonder... why not just add wetting agents to all container plants with ever repotting (they don't last forever).  If I search for 'wetting agents' I get a mix of:

 1) scientific articles not specific to agriculture talking about wetting agents in a general chemistry sense
 2) various soil wetting agents for sale
 3) instructions on how to make your own wetting agents, seeming to always be detergent soap + water

So, we all know plants don't like salty soil, so dumping soap into the soil doesn't sound like a good idea at all to me.  Of the many wetting agents for sale, I can't really understand the pros and cons of different types.  Anybody have experience with this?

Is there a low cost wetting agent that I can safely apply to my container trees?

I heard keledang season is around now, no clue about cherapu. 

My mango tree has a ton of fruitlets now.  I have yet to get a real crop because the first two years it bloomed the fruit all fell off before maturity, and last year it barely bloomed.   I think I had read that mango trees should not be watered while fruiting, is that true?  I understand ex. in India there's a dry season and it basically doesn't rain half the year and obviously mango trees do fine there. 

This is a grafted Mallika in-ground in a greenhouse, if it matters.  About 7ft tall

A relative from India who has grown and seen many jackfruit trees mentioned that I should prune some of the branches off my jackfruit tree to encourage it to flower.  Is there any truth to this?

I have a grafted jackfruit tree in-ground in my greenhouse that grows like crazy but hasn't flowered yet.  Trunk is about 4in diameter, and I have to prune it regularly to keep it under 10ft tall

Since moving many of my citrus and other container fruit trees into wide, shallow containers the two issues I am running into are

1) trees dry out quickly on hot days, which is expected
2) stability is a major issue at first when repotting into a shallow container.  I end up having to use strings, sticks, weights, etc to keep them from flopping over, especially when they are loaded with fruit

So, against all conventional wisdom, I am trying something which helps solve both of these issues - heavy clay.  My native soil is clay, I like to optimistically think of it as clay-loam but it is truly terrible when it comes to drainage.  When wet it forms a thick mud that will pull your boots right off if you step in it. 

Because I have recently been replacing my overly vigorous in-ground citrus trees with grafted-onto-flying-dragon clones, I end up with extras I no longer have use for.  These extras become subjects of sometimes cruel experiments. 

While repotting a half dozen trees today (into containers 3-4in deep), I added increasingly large amounts of clay soil to the usual free-draining mix.  The last few received almost entirely clay.  I watered them and a half hour later they were still saturated mud, I didn't keep waiting to see how long it would take to drain fully.  The heavy soil definitely helps keep them upright without outside support.

My hope is that the clay soil will be acceptable for these wide shallow containers, my reasoning being that I can control how often they receive water (because they are greenhoused) and because of the shallowness they may still receive enough oxygen from the air, and the plants transpiration plus air evaporation will keep them from becoming stagnant.  Trifoliate Orange is supposed to be one of the better rootstocks for clay also, I have read. 

Why go through this trouble to accomodate atypical containers?  It is mostly that I like the appearance of the tray style trees, that it eliminates the aggravation I have with discovering cylinder-pot trees have large dry spots or overly wet soil deep in their container, and that it lets me hang them up in the air without constantly hitting my head on the bottom of the pots. 

My in-ground in-greenhouse citrus trees thrive in this soil, but they have no perched water table.  I will report back how things work out. 

My grafted Bruce canistel set a single fruit that I've been watching for months.  It finally dropped on its own today and I found it on the greenhouse floor.  It is really tasty, outermost flesh is a bit dry but gets significantly moist towards the inside and much better than the ones I found lying on the ground at Fruit & Spice park (which were more dry and latex-ey). 

I'm very pleased!  There are many more new fruitlets that have formed in the past month so I expect a significant crop next year.





here it is on the tree a month or two ago when it started becoming yellow.  This tree is about 4ft tall and wide

I have seedlings of Ross Sapote, Lucuma, Olosapo that are all happy and healthy, but as space becomes tight I am wondering how long I might have to wait for fruit, and how big these will be by that time? 

I've seen grafted Ross Sapote for sale occasionally, but not the others. I've never tried the fruit of any of them, only canistel, and starting to doubt it's worth the wait just to try them.  It might make more sense to fly somewhere that has them in season!

It's shame as they are such nice looking trees.

Not often you see tropical fruit in the news so I thought I'd share this link.  This might be common knowledge to people on this forum, I don't know a lot about marang.  I don't think I've seen the wild type discussed here.

https://www.inverse.com/science/indigenous-knowledge-botany-plant-species

article text:

Here’s the background — In the gardens of homes in Borneo and the Philippines, it’s not uncommon to find a cultivated sweet fruit tree with thick pulp that bears a strong resemblance to jackfruit and breadfruit. The official scientific name for this tropical plant is A. odoratissimus, though locals refer to the plant by more colloquial names like marang and tarap.

An eighteenth-century Spanish friar who researched botanical plants in the Philippines, Manuel Blanco, was the first person to formally describe A. odoratissimus. Nineteenth-century Italian botanist, Odoardo Beccari, also later described two mature fruit specimens that scientists associate with A. odoratissimus.

Botanists also knew a wild relative of this tree existed that was somewhat different from the domesticated variety, but scientists simply thought it was a variant of the same species. The wild relative contained smaller, less-sweet fruits with thinner pulp and longer hairs.

But unbeknownst to scientists, Indigenous communities in Borneo and the Philippines had long classified A. odoratissimus as not one species, but two clearly separate species, with each fruit tree clearly marked by distinct features.

The Iban people in Sarawak — a Malayasian state in Borneo — recognized the cultivated and wild varieties of the plant as two species: lumok (cultivated) and pingan (wild). The Dusun people of Sabah — another state in Borneo — similarly recognized these plants as separate species known as timadang (cultivated) and tonggom-onggom (wild).

“I think that scientists working on these plants were not aware of the Indigenous classification system, because scientists have not often engaged with that type of knowledge,” Gardner says.

What’s new — In this latest study, Gardner’s team set out to bridge the gap between scientific and Indigenous knowledge. Specifically, they sought to scientifically verify whether these two plants, were, indeed, two genetically distinct species.

Through their research, the scientists confirmed the traditional knowledge of the Dusun and the Iban: The wild pingan is genetically distinct from the domestically cultivated plant lumok.

“The plants have noticeably different fruits which were evident to Indigenous people who were constantly around the plants but were not evident to scientists working largely from preserved specimens,” Gardner says.

With this study, science now formally recognizes and validates pingan as its own separate species. Therefore, pingan needs a scientific name so it can fit with the Linnaean taxonomy, the standard of scientific classification which Swedish botanist Carl Linnaeus established in the 1700s. Gardner’s team settled on A. mutabilis, a reference to the Italian botanist Beccari’s research on the plants in 1885.
Species tree figure from the study
A species “tree” showing the genetic distinction between and geographic origins of the two fruit species, known colloquially to Indigenous people as pingan and lumok. Gardner et al/Current Biology

How they made the discovery — In 2013, the researchers began their fieldwork in the Malaysian state of Sabah in Borneo before expanding to other areas. Gardner was intrigued by the unique plant, A. odoratissimus, especially for its delicious taste.

“We wondered whether there were any genetic differences between cultivated and wild plants,” Gardner says.

But the scientists really honed in on the Indigenous distinctions between the two plants in 2017, when they started collecting plant samples with two Iban field botanists, Jugah anak Tagi and Salang anak Nyegang, who are also co-authors on the study. Their collaborators from the state of Sabah in Borneo, field botanists Postar Miun and Jeisin Jumian, also confirmed that the Indigenous Dusun recognize the plants as two separate species.

“These findings led us to realize the importance of considering indigenous vernacular names in thinking about species limits,” Gardner says.

So, Gardner’s team used genetic sequencing to confirm the Indigenous classification of these two plants. Using field samples collected from Borneo, the scientists deployed a method known as target capture, which enriches DNA and allows researchers to efficiently sequence genes from the plant. This method allowed them to analyze the Italian botanist Beccari’s botanical samples from the 1800s, comparing them to modern plants.

“Because the target regions do not need to be on intact fragments, this method is suitable even for old samples with degraded DNA,” Gardner says.

Using these methods, the scientists were able to confirm there were “two distinct genetic clusters” for lumok and pingan.

Why it matters — The study’s publication is timely as scientists are collaborating more with Indigenous communities on projects ranging from gauging wildfire risk to sucking forever chemicals — chemicals known as “per- and polyfluoroalkyl substances” that linger in the environment for years — out of the ground. With this new study, we can add another area of scientific research where Indigenous knowledge will prove invaluable: species classification.

“People who live close to plants and see them on a daily basis have a different kind of knowledge about them that is different from and complements the way scientists think about plants,” Gardner says.
Tropical rainforest in Sabah, Borneo
The researchers conducted their fieldwork and collected plant samples from the Malaysian state of Sabah in Borneo. Getty

What’s next — To best protect a species, researchers must classify it scientifically within the Linnaean taxonomy. To conserve a species, scientists must name it, otherwise, it won’t appear on the IUCN Red List — the official list of plants and animals that conservation organizations use to classify endangered and threatened species.

But current scientific classification is lacking, and we can partner with Indigenous communities to fill in the gaps in our knowledge of species, the study argues.

“While Linnaean taxonomy offers a broad framework for global comparisons, it may lack the detailed local insights possessed by indigenous peoples,” the study authors write.

By marrying scientific knowledge with Indigenous classifications, we could potentially protect species from extinction. Due to manmade trends like global warming and deforestation, species are disappearing nearly every day. The UN reported in 2019 that one million animal and plant species faced extinction.

Gardner says that scientists are often already working with Indigenous guides when they conduct fieldwork, so it would be a natural next step for researchers and Indigenous communities to collaborate to classify species.

“This kind of collaboration can improve our understanding of biodiversity and can improve recognition of the contributions Indigenous people have been making to science all along,” Gardner says.

Of all the popular eugenias this is the only one I have been unable to find.  If anybody knows a source I would be grateful.