Two of the papaya trees on my farm are producing multiple fruit at each leaf node. Is this multiple fruit a response to environmental conditions or do some varieties simply bear fruit this way?

Both of these trees are volunteers spread by birds and/or bats.  All my other papaya trees have a single fruit per leave node.  Here's the first tree:



This second tree is doing it too, but the stems are hidden due to the number of fruit:


What's going on?

John

I need help deciding the most appropriate fruit to grow on my hobby farm. I want to focus on fruits that would be well-adapted to my climate and also be tasty.  The 'top fruits' poll on this forum was helpful, but I'd appreciate more suggestions. 

First, a little about the growing environment:
The farm is tropical (18 degrees south) and in an intermediate rainfall area (wet season and dry season).   Droughts in the dry season rarely last more than a month.  Soil is mostly clay/loam, hilly but with some bottom land with a shallow water table.  It is low elevation (seaside) but prevailing winds come from inland at this location so no significant salt  in the air or soil.

     

The fruit growing is mainly for my own enjoyment.  However, it is also possible that some day the land might be subdivided for residential so I've planted a lot of citrus, mango and avocado, since those are staples here and I know I can sell the fruit.  I think it's too tropical for lychee and cherimoya.

In a few weeks, I will be visiting the U.S. and want to bring fruit seeds back to Fiji.  I'll be searching the Asian and Hispanic markets around Dallas, Texas, and also plan to mail order seeds.  Unfortunately, I can't bring green wood back to Fiji due to biosecurity concerns.   I have almost everything available here in Fiji.

I've only had the farm for a year and half, so not much is fruiting.   Here's what's on the farm now:

Abiu  6
African Pride (Custard apple) 1
Avocado (Local) 44
Banana – Big  18
Banana – Lady's Finger  1
Black Sapote 1
Brazilian Cherry 2
Breadfruit 3
Bullocks Heart (American Custard apple) 2
Cashew  3
Cinnamon  6
Citrus – Cleopatra Mandarin   12
Citrus – Cutter Valencia  2
Citrus – Dancy Tangerine  2
Citrus – Grapefruit Ruby Red 6
Citrus – Harvey Lemon  2
Citrus – Kumquat (round) 1
Citrus – Late Valencia 24
Citrus – Lee Mandarin  2
Citrus – Meyer Lemon  50
Citrus – Seedless Lime  37
Citrus – Lisbon Lemon  2
Citrus – Miniola Tangelo  11
Citrus – Olinda Valencia  12
Citrus – Orlando Tangelo  2
Citrus – Page Mandarin  2
Citrus – Rough Lemon  5
Citrus – Satsuma Mandarin  9
Citrus – Fiji/Unknown Mandarin  23
Citrus – Washington Navel  18
Citrus – West Indian Lime  2
Cocoa 8
Coconut – Dwarf 10
Coconut – Tall  50
Coffee 5
Curry Tree  3
Custard Apple (US Sugar Apple) 9
Davidson Plum  2
Dawa (Fijian Longan)  2
Dragon Fruit (White interior)  2
Fig  2
Ginger 2
Granadilla  4
Guava (3 types)  6
Ivi  2
Jackfruit  3
Jacoticaba  4
Jamun – white 1
Jamun – back 2
Kavika (Rose apple) 6
Langsat  1
Lemon Grass  2
Lychee  3
Macadamia  2
Mamey Sapote  1
Mango (2 varieites) 80
Mangosteen  7
Miracle Fruit 1
Mulberry  4
Neem 2
Noni  3
Nutmeg 4
Papaya (Hawaiian & local)  19
Passionfruit (yellow and purple) 19
Pepper, black 4
Pineapple (2 varieities) 30
Plantain 4
Pomegranate  2
Rambutan  4
Sandalwood  4
Sapodilla  4
Soursop  8
Star Apple  4
Starfruit (Carambola)  5
Sugar Cane (purple) 2
Tamarind  2
Tarawau  2
Tavola   2
Turmeric 2
Vanilla    2
Vutu     3
Wi  2
Yaqona (Kava) 2

What else would be good to grow?

Thanks,  John

Last week I received the results of soil quality analysis performed by my Department of Agriculture.  I'm a little concerned that the electical conductivity is so low, at 0.05 compared to what the report listed as the good range of 0.40-0.80.  Are there any negative consequences of having such a low electrical conductivity?

My soil a dark volcanic clay-loam.

pH (1:5 water)                 6.5   Good  (Ideal is 5.6-6.6)
Elect. Conductivity (1:5 water; mS/cm)  0.05  Very Low   (0.40-0.80)
Total Carbon (%)                 4.7   Good  (4-10%)
Total Nitrogen (%)                0.4   Good    (0.3-0.6)
Olsen Available Phosphorus (mg/kg) 4.1  Very Low   (20-30)
               
Exchangeable Bases (me/100g)               
Calcium          17.1      High (ideal is 2-10)
Magnesium      4.3      High  (1-3)
Potassium          0.18      Low  (0.3-0.6)
Sodium         0.07      Very Low  (0.3-0.7)
               
Extractable Traces (mg/kg)               
Iron               57.5     Very High  (ideal is >4.5)
Manganese     30.6     Very High   (>1.0)
Copper          0.1     Low    (>0.2)
Zinc         0.8     Low    (>1.2)

I don't know much about soil tests, so any observations and suggestions on improving the soil for citrus, mango and avocado would be appreciated.

John

A few weeks ago I cleft grafted 103 sour orange rootstocks with sweet oranges, mandarins and tangelo scions.  I am pleased that 92 of the 103 grafts were successful (my highest success rate so far), but I wanted to learn why 11 grafts failed. 

Today I unwrapped them, and here's what I found:

On the graft below, I think the scion was a little too thin.  I should have watched more carefully and put it on a thinner rootstock.


This rootstock was not straight, and when I cut into it from the top, the cut followed the uneven grain so cambial contact was limited.  I should have cut the rootstock where it was straight.


Here's another one where the scion appeared to be too small:


The bottom of this scion should have been cut thinner.  It was forcing the two sides of the rootstock apart instead of clamping the scion in place.  The rootstock cut was also not centered properly.


This one is interesting, because the bottom of the scion appears to have some life in it.  I can't figure this one out.


One thing I learned from this:  The scion should always be slightly thicker than the rootstock.  This allows better contact between cambiam layers.  If they are the same size, and both scion and rootstock are cut down their middle, the very bottom of the scion is the only place that can make cambial contact.  Someone on a forum (either this one or the Citrus Growers) suggested the scion should be thicker, but I haven't read it in any of my books discussing cleft grafts.  This drawing I made to clarify the concept.  When the scion is slightly thicker, cambial contact should be achieved near the two areas circled.
 

I also had either a compatability problem or a bad scion stick because only one out of 5 Orlando Tangelo was successful (vs. 90+% on the others)

Thank you for allowing me to share this with you, and for reading this far.  I'd appreciate any comments or suggestions relating to cleft or veneer grafting.

John

One of my soursops has brown sections on many leaves.  What might it be?  How to treat?

Not an Oscar-quality photo, but it was windy today and I only took this one shot:



It is not affecting my other soursops, but looks similar to a leaf problem I have on all my rambutan (which I've almost given up on due to this problem).

The season now is dry and cool, which means 70-80 degrees f, but high humidity.

Any clues appreciated!

Thanks, John

Some of my mango rootstock seedlings have developed a light grey colour. See photos below.  The leaves eventually wilt and die.  It doesn't look like the powdery mildew photos I've seen on the web.  What is this?  How to treat?





It's the cool, dry season now.  None of my mature mango trees show this problem.

Thanks,
John

I am amazed at the number of new mango varieties that have become available in recent years.  Are most of the new varieties developed the old fashioned way, from natural or controlled seed hybridization and limb sports?  Or are they mostly a result of modern techniques such as gene sequencing and other genetic modification methods?

A lot of amazing genetic 'improvements' have been made to corn, soybean and other crops.  Are our tropical fruits resulting from the same processes?

I have one mamey sapote seed and want want to plant it.  Boning's book "Florida's Best Fruiting Plants" advises to plant the sharply pointed end down, but the two ends of my seed appear very similar in regards to pointyness.  Would someone kindly elaborate on which end goes up or down?

One end shows a small stem scar.  That end might be slightly more rounded, but not much.  Please help.

Thanks,
John

I have six small star apple trees that have been in the ground 4-6 months.  They all tend to have curled leaves (see photo below).  Is star apple very drought sensitive?  They receive water regularly, and the leaves do not flatten out after watering.  Some are in full sun, other partial shade.  Maybe they need more shade the first few years?  Any ideas?



Thanks,
John

I am growing mango from seeds to use as grafting rootstock.  The seeds are a hardy "bush mango" variety and are polyembryonic.  When more than one shoot spouts up, it is best to pinch off the slower-growing one immediately, try to pull the one up without damaging the primary shoot, or let 2 or 3 grow a while before culling them down to one?  What's the best way?

Thanks,
John