Olympian breba update

shevitz said:
Thanks for that article. The main reason that applies is water. This tree is on irrigation and gets watered regularly. I’ve got 2 x 1 gallon per hour emitters. I was watering three times per week for 20 minutes at a time. So I guess the tree was getting 2 gallons per week. Except I’ve also been watering it manually and probably giving it another five or 10 gallons on the weekend but not measured. The photos above are representative of the size of the tree. It’s been about 90° during the day, but there is a rock mulch with landscape fabric underneath it. Is there a rule of thumb how many gallons a week a tree the size should be getting? I would feel terrible if I’ve been underwatering it. It would be so easy to fix. I just boosted the irrigation to every day for 20 minutes which boosts it to a little under 5 gallons a week. The tree looks extremely healthy otherwise and has no yellowing or leaf drop.
Click to expand...

From the article:

"The most common reason for figs dropping off your tree or not ripening properly is a lack of soil moisture. Although fig trees are one of the most drought-tolerant fruiting plants, consistent soil moisture is required for ripe, plump, and tasty figs."

The leaves look good but...a gallon or two a day for an in-ground tree is not much water. I doubt much of it is getting to the roots. You can dig down an inch or two before watering. If the ground is dry, it's time to water. Additionally, 2 emitters for an inground tree isn't enough. I would bet there are large areas of soil around that tree that remain dry. I use a minimum of 10 emitters for an inground tree that size, spaced close enough to saturate all surrounding soil.

I live in Arizona, where temps are hot. Our humidity levels are low. Our soil is mostly rocks and clay. I amend my trees with composted steer manure, give them a very small amount of 10-10-10 fertilizer in early spring. They produce very well. My best producing trees are most likely Brown Turkey. I got cuttings from a neighbor in another town many years ago. BT and Olympian are supposedly similar.

I water heavy. Currently twice each week. When temps exceed 100 degrees for extended periods, I will water 3 times a week. This allows things to dry out a little between waterings. I put out anywhere from 30 to 40 gallons per tree when I water, but my trees are older and larger. Watering heavily but slowly allows the water to penetrate deep into the soil, so when things dry out near the surface, there is usually some moisture down deep. Also, understand that roots zone normally extends much further out from the width of the branches and foliage of the tree. You want to water wide and deep. That's why I removed my landscaping fabric 4 to 5 feet out from the base of my trees. That fabric impedes water and amendments. The roots need water.

That's how I do it.
 
Last edited:
Dave The Fig Guy said:
From the article:

"The most common reason for figs dropping off your tree or not ripening properly is a lack of soil moisture. Although fig trees are one of the most drought-tolerant fruiting plants, consistent soil moisture is required for ripe, plump, and tasty figs."

The leaves look good but...a gallon or two a day for an in-ground tree is not much water. I doubt much of it is getting to the roots. You can dig down an inch or two before watering. If the ground is dry, it's time to water. Additionally, 2 emitters for an inground tree isn't enough. I would bet there are large areas of soil around that tree that remain dry. I use a minimum of 10 emitters for an inground tree that size, spaced close enough to saturate all surrounding soil.

I live in Arizona, where temps are hot. Our humidity levels are low. Our soil is mostly rocks and clay. I amend my trees with composted steer manure, give them a very small amount of 10-10-10 fertilizer in early spring. They produce very well. My best producing trees are most likely Brown Turkey. I got cuttings from a neighbor in another town many years ago. BT and Olympian are supposedly similar.

I water heavy. Currently twice each week. When temps exceed 100 degrees for extended periods, I will water 3 times a week. This allows things to dry out a little between waterings. I put out anywhere from 30 to 40 gallons per tree when I water, but my trees are older and larger. Watering heavily but slowly allows the water to penetrate deep into the soil, so when things dry out near the surface, there is usually some moisture down deep. Also, understand that roots zone normally extends much further out from the width of the branches and foliage of the tree. You want to water wide and deep. That's why I removed my landscaping fabric 4 to 5 feet out from the base of my trees. That fabric impedes water and amendments. The roots need water.

That's how I do it.
Click to expand...
So you are watering 100 gallons per week peak season?
 
I don't think my EBT has any breba on it but it is loaded with main crop. I can't wait. Maybe I will make a peach cobbler using figs, Lol
 
shevitz said:
I am terribly afraid that my tree is going to drop its brebas🙁. They are turning yellow, and I don’t think it’s in a good way. I could be wrong, but I’ve got a bad feeling about this. Otherwise, the tree is incredibly happy and healthy putting on lots of growth and main crop figs. I think they’re getting plenty of water and they have long acting fertilizer. I don’t know what’s up other than maybe it got too hot too quickly, but once they get to a certain size, they seem to be turning brown. last year’s main crop looked nothing like this. They also don’t appear to be reaching full-size. Thoughts? Anything to try to salvage this? It’s possible that I had a few brebas last year, and they all dropped as well.
Click to expand...
Good looking tree i think ripening
 
Brebas usually rarely hold for me, that seems to be the case for most people too so don’t feel too bad about it. It’s so early in the season and lots of variables come into play so the trees usually drop them here on the east coast but that shouldn’t be the case for your main crop! :)
 
BNaula1 said:
Brebas usually rarely hold for me, that seems to be the case for most people too so don’t feel too bad about it. It’s so early in the season and lots of variables come into play so the trees usually drop them here on the east coast but that shouldn’t be the case for your main crop! :)
Click to expand...
I hope so. It’s just heartbreaking to watch 90 figs turn yellow and die.
 
shevitz said:
Watched it, and it was nice. I’m not exactly sure what the lesson is except keep your tree watered and fertilized. I didn’t get much more out of it than that. I’m pretty sure my tree was underwater so at least I’m giving it that.
Click to expand...

My takeaway is the amount of water, in and of itself, is irrelevant. The goal is to create and maintain a healthy growing environment. Moist but not soggy soil, plenty of sunlight, and appropriate nutrients. Different climates and soil conditions require different methods to accomplish that.
 
5 gallons per week is about what a large tomato plant will drink with 90f and a low dew point.
An emitter giving only 3 pints at a go is probably loosing a lot to surface evaporation, but the devil is in the details.
You need to saturate the upper dry rootless layer before any moisture even starts to hit the root zone. Also, you should check the moisture depth and spread before and 12-24 hours after irrigating, it really does take this long to wick around and find its balance. (This is mostly while establishing a baseline or big changes in seasonal weather, you don't need to dig infinite test holes into the future.)

Trees have roots several feet deep if the soil allows, even wheat(a deep rooted annual) can go 5 feet deep when approaching maturity.

Emitter spacing and flow rate is entirely dependent on soil type. My soil is so sandy that emitters are impractical because there is very little spread, other soils I've seen get 2-3 feet circles from each emitter.
Area to water as a basic starting point is a circle radius about 1.0-1.5 times the branch length. But it depends on pruning history though, roots keep going when branches are trimmed back so 2× may be appropriate for an old tree.

There are 3 or 4 soil moisture levels of interest in agriculture, oven dry, permanent wilt point, field capacity, saturated. Saturated has no air space, shiny surface and if disturbed it becomes mud. If you let a covered sample [no evaporation] of saturated soil freely drain by gravity for a day or two until it no longer drips or looses weight, then you reach field capacity.

Field capacity has some air and almost zero water potential (Think of it like pressure to extract some water, or how hard a root needs to work to get positive uptake.), soil can sit in this state for a long time if without plants and protected from evaporation.

Permanent wilt point is the point where plants can't get enough water from the soil to recover at night with high humidity, the plant isn't necessarily permanently damaged it is just that it can't recover just by removing the evaporation of hot sun and wind.

Oven dry is self descriptive, but is useful as a zero reference point for characterizing a soil type's water capacity and perm wilt point.

Field-capacity-water percent minus the perm-wilt-point-water percent gives total available water [TAW] as percent of soil volume. Except for extreme clays and sand TAW is typically between 10-18% by volume (eg. 12% Meaning 1 cubic foot of soil can hold 0.12 cubic feet [0.94 gallon] of plant available water.)

Staying between field capacity and perm wilt will keep your plant alive but frequently dipping into the dryer end will make the plant work harder and reduce yields.
The change in work/stress is highly non-linear though so most of the stress happens in the dry third of the TAW. So using a soil with TAW of 12%, using the first 4% takes you from a starting water potential of -20 kPa down to -60 kPa(hardly noticeable), using 8% takes it down to -130 kPa (probably only has a noticeable effect during high evaporation conditions), while using the whole 12% takes it down to -1500 kPa (Which will likely cause complete fruit drop and even some leaf drop even if temps are modest and humidity high.)

OKstate soil water info basically says the above but has charts and more detail.
 
Capistan said:
5 gallons per week is about what a large tomato plant will drink with 90f and a low dew point.
An emitter giving only 3 pints at a go is probably loosing a lot to surface evaporation, but the devil is in the details.
You need to saturate the upper dry rootless layer before any moisture even starts to hit the root zone. Also, you should check the moisture depth and spread before and 12-24 hours after irrigating, it really does take this long to wick around and find its balance. (This is mostly while establishing a baseline or big changes in seasonal weather, you don't need to dig infinite test holes into the future.)

Trees have roots several feet deep if the soil allows, even wheat(a deep rooted annual) can go 5 feet deep when approaching maturity.

Emitter spacing and flow rate is entirely dependent on soil type. My soil is so sandy that emitters are impractical because there is very little spread, other soils I've seen get 2-3 feet circles from each emitter.
Area to water as a basic starting point is a circle radius about 1.0-1.5 times the branch length. But it depends on pruning history though, roots keep going when branches are trimmed back so 2× may be appropriate for an old tree.

There are 3 or 4 soil moisture levels of interest in agriculture, oven dry, permanent wilt point, field capacity, saturated. Saturated has no air space, shiny surface and if disturbed it becomes mud. If you let a covered sample [no evaporation] of saturated soil freely drain by gravity for a day or two until it no longer drips or looses weight, then you reach field capacity.

Field capacity has some air and almost zero water potential (Think of it like pressure to extract some water, or how hard a root needs to work to get positive uptake.), soil can sit in this state for a long time if without plants and protected from evaporation.

Permanent wilt point is the point where plants can't get enough water from the soil to recover at night with high humidity, the plant isn't necessarily permanently damaged it is just that it can't recover just by removing the evaporation of hot sun and wind.

Oven dry is self descriptive, but is useful as a zero reference point for characterizing a soil type's water capacity and perm wilt point.

Field-capacity-water percent minus the perm-wilt-point-water percent gives total available water [TAW] as percent of soil volume. Except for extreme clays and sand TAW is typically between 10-18% by volume (eg. 12% Meaning 1 cubic foot of soil can hold 0.12 cubic feet [0.94 gallon] of plant available water.)

Staying between field capacity and perm wilt will keep your plant alive but frequently dipping into the dryer end will make the plant work harder and reduce yields.
The change in work/stress is highly non-linear though so most of the stress happens in the dry third of the TAW. So using a soil with TAW of 12%, using the first 4% takes you from a starting water potential of -20 kPa down to -60 kPa(hardly noticeable), using 8% takes it down to -130 kPa (probably only has a noticeable effect during high evaporation conditions), while using the whole 12% takes it down to -1500 kPa (Which will likely cause complete fruit drop and even some leaf drop even if temps are modest and humidity high.)

OKstate soil water info basically says the above but has charts and more detail.
Click to expand...
So much useful information! Thanks for taking the time to share. Doing the math, a 6’ circle to a two foot depth, which is supposedly the feeder root depth of a fig tree, is 56.5 cu ft. With a 15% TAW, this becomes 8.5 cu ft water which is 64 gal which sure seems like a lot of water holding. Now the question is how much daily do I need to water to maintain this? I have landscape fabric and rock beneath the tree. So while the soil gets hot, but I haven’t measured the temp yet, the is no direct sun or wind exposure. If evapotranspiration is 1.5” per week, that number is 3.5 cu ft or 26 gal. I would be replacing about half of the water every week. It will be trial and error, but these numbers give some useable benchmarks. Thanks!
 
shevitz said:
So much useful information! Thanks for taking the time to share. Doing the math, a 6’ circle to a two foot depth, which is supposedly the feeder root depth of a fig tree, is 56.5 cu ft. With a 15% TAW, this becomes 8.5 cu ft water which is 64 gal which sure seems like a lot of water holding. Now the question is how much daily do I need to water to maintain this? I have landscape fabric and rock beneath the tree. So while the soil gets hot, but I haven’t measured the temp yet, the is no direct sun or wind exposure. If evapotranspiration is 1.5” per week, that number is 3.5 cu ft or 26 gal. I would be replacing about half of the water every week. It will be trial and error, but these numbers give some useable benchmarks. Thanks!
Click to expand...
 
You must log in or register to reply here.
Back
Top