Return to the Fig Forum | Post a Follow-Up

 o
Consequences and benefits of over fertilization.

Posted by thisisme az9b (My Page) on
Thu, Apr 15, 10 at 13:54

This year I fertilized my trees with Osmocote Citrus and Avocado fertilizer like I have for years. This year was different though as the fertilizer had been left out and was rained on a couple times last winter. Now my fig trees are growing like crazy but most of them have very few figs compared to last year. I think this is a good thing for my smaller trees. However I'm not happy with the results on my mature trees as I have lost the breba crop. With any luck there will be a bumper main crop to make up for it but I will be getting rid of the old fertilizer so this does not happen again.


Follow-Up Postings:

 o
RE: Consequences and benefits of over fertilization.

  • Posted by tapla z5b-6a MI (My Page) on
    Thu, Apr 15, 10 at 14:34

Are these trees in the ground?

Al


 o
RE: Consequences and benefits of over fertilization.

Hi Al, they are all in 15-25 gallon pots and already have 8-18" new growth this season.


 o
RE: Consequences and benefits of over fertilization.

  • Posted by tapla z5b-6a MI (My Page) on
    Thu, Apr 15, 10 at 15:06

You have me wondering. Initially, I assumed that they were in containers and that the reason wasn't fertility related, rather, that it was probably due to tight roots; but, now that you reveal you observed that much extension of the branches, it doesn't sound like tight roots ...... NOR, does it sound like a fertility issue. If the plant didn't have adequate nutrition, or if it was badly root bound, it wouldn't be extending like that. Just for grins - how long since the last repot, and did you root-prune? Can you tell me what the NPK ratio of the fertilizer is and what other elements it contains? Is it a soluble? granular slow release? organic?

Al


 o
RE: Consequences and benefits of over fertilization.

Hi Al, For the most part the 15 gallon trees were in 5 gallon containers in the Fall of 2008. The trees in 25 gallon containers were in 15 gallon containers in the Fall of 2008.

I just looked and I did not use Osmocote. I used Vigoro Citrus & Avocado Plant food 12-5-8 plus minors. Its a slow release granular fertilizer and the bag was rained in at least twice. I had to bang the bag around to break the clumps apart before fertilizing mid February. I guess the fertilizer started releasing in the bag and caused the trees to get to much nitrogen all at once. They are growing like crazy. With our long season I could easily see 6+' of growth this year.

The link below lists all the minors.

Here is a link that might be useful: Vigoro Citrus & Avocado Plant food 12-5-8 plus minors


 o
RE: Consequences and benefits of over fertilization.

Oh I also forgot to mention that I put about 1/2 gallon of de-smelled composted steer manure over the fertilizer and added compost over that. I do that every year though and have never had this kind of growth or lack of fruit.


 o
RE: Consequences and benefits of over fertilization.

  • Posted by tapla z5b-6a MI (My Page) on
    Thu, Apr 15, 10 at 17:53

Lol - I guess that explains how the excessive N came into play. ;o)

Al


 o
RE: Consequences and benefits of over fertilization.

Hi Thisisme,
im curious as to what Al has to say as he is the brains here not me by a far margin.
I just like to throw this out though from what i have noticed over the years with my plants. I have gone up in size to bigger containers most recently 2 of them from 10 to 30 gallon several winters ago without doing a root prune and the following year they took off and i said to my self it was not the fertilizer although it took more because of pot size to get it to drain out which i always do and then stop.
The thought i had why my plants took off was because the roots had that much more room to spread and therfore made the tree respond in a good way.
As for breba well in my zone i just dont get hardly any.
I did screw up one plant when i root pruned it put back in same container and left the canopy untouched for the first time in 7 years it droped more than half the main crop while my other plants were normal.
Anyways this is not an answer just what mine did at the time. Now im keeping my newer trees smaller and useing smaller containers and keep them in check by root pruning and limb pruning as the big containers are getting harder to move about as im not getting any younger.
Martin


 o
RE: Consequences and benefits of over fertilization.

This is a good post for us container growers and am looking forward to Al's input. I'm noticing similarities to what Thisisme posted in my pots but have mistakes to add so I will not hijack this post and will start a new post in the coming days. hopefully between the 2 posts we can fig-ure this out so it will not be repeated by others including myself
Sal


 o
RE: Consequences and benefits of over fertilization.

Hi Martin, we have a long season and I usually get nice crops of both breba and main crop figs. I'm pretty sure the problem is that the fertilizer sat in the plastic bag and got good and soaked 2-3 times over a couple of months. No doubt the fertilizer started releasing and my trees got 2-3 months worth all at once. I just wanted people to know what can happen as you can get good growth on young trees if you don't burn them. I also wanted people to know what the consequences are on fruit production when a tree goes into hyper vegetative growth.

Large pots are preferred here in the desert where summer temps can be 110+ in the shade for weeks or even months at a time. Couple that with extremely low humidity and it can dry out a tree and a pot sitting in full sun very fast. A tree dolly is on my list this year as I found a good one under $ 200.00 delivered. Just one more thing I'm saving for.


 o
RE: Consequences and benefits of over fertilization.

Hi Sal, if the subject is over fertilizing trees in the ground or in a pot I would not be offended. I was hoping others would have some experiences to share either good or bad. There is not much I can do but watch them grow now as I would not be surprised if the six month slow release fertilizer dumps its full load in the first three months.

Two questions I'm hoping get answered are...

Has anything like this happened to anyone else?

If so did you get a huge main crop on all of the new growth?


 o
RE: Consequences and benefits of over fertilization.

For what this is worth, and it may not be worth all that much, I had only seven berba figs on my kadota and the black mission failed to fruit all together. Both were 4' trees when planted last September and I would have expected better from both.

I am being told our spring is cooler than usual here in AZ. Could this be a factor?


 o
RE: Consequences and benefits of over fertilization.

Hi wabikeguy I don't think that would be a problem as our cooler Spring weather amounts to temps in the 70's-80's and we are in the low 90's now. We are warmer here in our cooler than normal Spring than most of the nation is in a normal year. I have a 7' tall 4 1/2' wide Black Mission and it only has two fruits that stayed on it.

I guess I should make mention that my trees had lots and lots of little figlets. After I fertilized nearly all of them dried up turned an ugly tan-ish color and when I touched them they fell off.


 o
RE: Consequences and benefits of over fertilization.

After re reading the top of thread and more newer post within i think you answered your question about the growth with the slow release fert.
Im not familar with its use, but it does sound logical to me if wet several time it would get activated couple with the manure , compost you got fast growth.
Im sure Al will explain how all this works in conjunction with each other in much further detail that i will enjoy reading for more knowledge.
Im wondering and hope Al answers since your climate is so hot and i would think your pots could dry out fast if you could flush it out with more heavy waterings along with pruning the branches back somewhat if they continue to grow at a faster than what would be normal rate.
I trust Al's expertise.
Martin


 o
RE: Consequences and benefits of over fertilization.

  • Posted by tapla z5b-6a MI (My Page) on
    Thu, Apr 15, 10 at 21:58

Thank you, Martin. I consider that a compliment.

This thread is a little confusing because in places we're talking about container size and how tight the roots are, and in other places, we're talking about nutritional issues.

Let me start by saying there are several kinds of 'slow release' fertilizers. When we talk about these types of fertilizers, we usually are talking about how they deliver N, because N is most used by all plants.

Slow release fertilizers may be either organic or inorganic. They are simply fertilizers that are characterized by a slow rate of release, long residual presence in soils, somewhat lower low burn potential, and low water solubility. FWIW, they cost more per volume of N than water soluble fertilizer. Several categories of slow release nitrogen fertilizers are commercially available, including:

Urea-formaldehyde, sulfur coated urea (release rate controlled by coating thickness), plastic or polymer coated, (release dependent on temperature and coating thickness), and natural organics fertilizers/soil amendments. There is some confusion throughout the industry because of terminology. Many refer to controlled release fertilizers as slow release. Indeed they are slow release, but I think it tends to help avoid confusion if we refer to the coated prills as CRFs and the granular fertilizers and organic soil amendments as 'slow release'. I realize a case can be made for using 'controlled release' and 'slow release' interchangeably, but I think the term CRF sets the prilled/coated fertilizers apart and puts them in a different category.

I'll let you guys ask your fertilizer questions, because I'm unsure exactly what they are, but in the meanwhile, I'll talk a little about vigor and vitality as it relates to root congestion and potting up vs repotting.

I'm going to try to use a numbered scale to illustrate approximately what happens to a trees vitality and vigor in a container over time. I know I've posted the next paragraph here before, but I think it's important to understand the difference between vigor and vitality, and how each relate to the growth.health of trees.

Some might have noticed my regular use of the term vitality when I write. It is actually a plants vitality that we can have an impact on, not its vigor. Vigor is constant in trees and other plants. Mother Nature provides every plant its own, predetermined level of vigor by building it into each plant. Vigor is the genetic potential every plant is encoded with, and its measure is the plant's ability to resist stress and strain. Vitality, in contrast, is variable - a dynamic condition that is the measure of a plant's ability to cope with the hand it's dealt, culturally speaking. A good way to look at the difference between vigor and vitality is to look to genetics for the level of vigor and to things cultural for the plants vitality. It's up to us to provide the cultural conditions that will ensure our plants' vitality. Vigor and vitality are distinctly different, and a good case could be made that they are unrelated, but there is no need to delve deeper into that point. A plant can be very vigorous and still be dying because of poor vitality. Far more often than not the term 'vigor' or 'vigorous' is misapplied, where in their stead the terms 'vital' or 'vitality' would have been more appropriate. Poor vitality is what we witness when our plants are growing under stress or strain and in decline. (My appreciation to the late Dr. Alex Shigo for his works, which have helped distill my understanding of stress, as opposed to strain, and vitality as opposed to vigor.)

Let's assign a tree a level of potential vitality of 1 -10, with 1 being a dead tree and 10 being a tree with perfect vitality and achieving its maximum potential growth. Right off, from a practical standpoint we can eliminate the possibility of a tree being a 10 in a container. It's just too difficult to get everything perfect and have it remain perfect all the time. I'll assign a level of 8 as the best we can hope for in a container.

Since we're looking at repotting, potting up, and root congestion, let's imagine that all conditions are perfect except the idea we're focusing on for the moment - roots. In order for your tree to continue to at a level of 8, root congestion has to be kept to a minimum. Research shows (not mine) that at approximately the point where the root and soil mass can be lifted from the container intact, growth begins to be negatively affected. This means that if we want to maximize growth and keep our plants growing at that illustrative level of 8, we need to pot up as soon as the roots/soil can be lifted intact. Research also shows that trees allowed to become root bound beyond this point will show their growth to be permanently affected. The reason this has been studied so carefully is the nursery trade has a vested interest in seeing their woody material gains caliper as fast as possible. Larger trunks mean more $s.

Setting the scene here, we have a tree in a pot and it's becoming root bound. When first potted as a cutting and while growing under our imaginary perfect conditions it grew at a level of 8. It's becoming more root bound now, and its vitality level is declining. It drops from 8 to 7 to 6 to 5, and you start to really notice it's stopped growing, stopped producing inflorescences, all the interior foliage is dying back ...... it's just generally declining.

Here is where you decide whether to repot (which includes bare-rooting and root pruning) or simply pot up. If you pot up, you see what you THINK is a big growth spurt, but in reality, we KNOW the tree cannot grow any better than 8. What you actually see is your tree changing from a level of 5 to a level of 7. You allow it to grow in that pot for another couple of years, over which time it declines to a level of 4. If you only repot, its growth improves with what you see as another spurt, but this time your tree only reaches a maximum vitality level of 6. Two years later, it's declined to a 3, and potting up brings it back to a 5.

After 5-10 years, your tree is so weak it's attacked by insects and/or disease and dies. You blame it on the insects or disease, but really it was the condition of the roots that was the actual cause behind the slide into oblivion.

Now, let's look at what happens if we do a full repot. Your cutting starts out at 8 and declines to a 5 over 2 years. This time however, you decide to do a full repot. Your tree sulks for two weeks, then takes off. Soon, it's growing at a level of 8, with plenty of room for roots. It declines to 5 over two years, you do a full repot, and the tree is restored to a level of 8 again. This can go on for as long as any of us are alive. This attention to roots is what allows bonsai trees to grow with near perfect vitality for hundreds of years and be passed down from generation to generation, while most of us struggle to keep trees even as genetically vigorous as figs happy in containers.

Figs and mulberry (same family) are probably the two easiest trees I've worked on, as far as roots go. They tolerate practically anything if you pay a little attention to the timing. I heartily suggest that you learn how to tend properly to the roots and do a full repot every 1-2 years - 3 years at most.

Are there any questions about repotting or specific questions about fertilizing?

Al


 o
RE: Consequences and benefits of over fertilization.

Al,Thanks for the very useful information.
Phil


 o
RE: Consequences and benefits of over fertilization.

  • Posted by chills Zone 6b Mi (My Page) on
    Thu, Apr 15, 10 at 23:24

I've got a problem with the common recommendation of removal of the larger roots, leaving as many smaller (fine) roots as possible. Every tree I've bare-rooted has thick roots coming off of the base of the stem, with smaller roots as you extend away from this point.

how does one remove thicker roots without losing the fine smaller roots? Should one try to remove approximately half of the thicker roots (or some other percentage) focusing on the thickest of the thick? should one remove the thickest root which generally emerges from directly below the stem? Should much of the goal be to leave much of the pot (below say the top 1/4th) largely empty of roots?

I'll leave my questions about timing for later as I'm tired and want to see the response to this first.

Thanks

~Chills


 o
RE: Consequences and benefits of over fertilization.

  • Posted by tapla z5b-6a MI (My Page) on
    Fri, Apr 16, 10 at 15:02

Roots are pretty much like branches in their tendency to break back. When you prune a thick root, it immediately starts producing fine roots from the stub you left. The trick is to remove a portion of the thickest roots each time you root prune. Obviously, you don't cut ALL the roots off, but to tell you the truth, figs are soo vigorous you almost could do that if you wanted to. It would just take an extra long time to recover, and it really serves no purpose, unless you're trying to prove how large of a tree you can force into the tiniest of pots. ;o)

My trees have a trunk with about 1-2" of roots growing horizontally off the trunk. There are NO roots growing downward from the bottom of the trunk. They are ALL horizontal off the trunk. After the roots are a couple of inches away from the trunk, I let some angle downward a little. At repot time, the entire bottom of the container will be filled with very fine roots. This is the IDEAL situation/condition for roots of containerized plants. It allows the maximum volume of fine, feeder roots.

Here are some basic guidelines for root pruning that you can build your program around:

* You want to eventually develop a rather flat root system, i.e. disc shaped.

* The first time you root-prune your tree, you may not be able to achieve this shape entirely.

* Basically, you can start by taking a saw to the bottom 1/3 of the roots and removing them - before you remove any soil.

* After the bottom 1/3 of the roots are removed, bare root the remaining roots. You don't want to be inordinately rough, but you needn't be all that gentle, either.

Photobucket

Some of the tools I use you can see in the picture above. The stainless root rake and the homemade nylon root pick work well to remove soil, but a sharpened dowel about the thickness of a pencil works very well, too. I also use a root hook, which isn't shown, but is, as you might guess, is made of steel, is hook-shaped and great for straightening/untangling roots. I often rely on Dramm brand Foggit nozzles when necessary, to help remove soil via water pressure. The other two tools are bonsai specialty tools, one designed for pruning roots (the stainless tool), the other for general pruning chores. A pair of bypass pruners will do the job.

It's very important to keep the fine roots from drying out after you start the work, So I have everything ready so I can work fast. I don't like to use water while I'm removing the bulk of the soil, so I try to pick a spot out of wind and sun on a humid day. If you think the roots could be drying out, spritz them or abandon the root stick in favor of a jet of water

* After bare rooting, you'll want to remove an additional 1/3 - 1/2 of the remaining roots. THIS is where you concentrate on large roots growing downward from the bole (trunk). Remove heavy roots that are trying to be tap roots and are growing downward. They serve no purpose in container culture other than as transport roots, and you'll have plenty of others to fill that job.

* When you prune the larger roots, prune back to a secondary root that is growing outward from the larger root. When you've removed the 1/3-1/2 of the largest roots remaining after sawing off the bottom 1/3 of the roots, focusing on creating a disc-shape, you're done with the pruning.

* Now, simply return the tree to the pot; add fresh damp soil; use the root stick to work the soil in around the roots so there are no air pockets; secure the tree so it doesn't move in relation to the pot. Securing the tree against wind and jostling fractionalizes the time it takes for the tree to reestablish.

* Water the tree in well and wait 2 weeks before you fertilize.

Chills - all you need to do is bring a couple of trees To Bay City and we can make short work of repotting them. You could do it now, if they're not yet pushing growth. I've been repotting for a month already, so another couple trees added to the 100 or so I've already done isn't going to make a whit of difference. All you need to do is call to set it up. ;o)

Al


 o
RE: Consequences and benefits of over fertilization.

Al I just want to Thank You for having the patience and sharing your vast knowledge. All I can say is that I follow your soil recommendation and root pruned this past year and my trees look great. I did put some CRF into potting mix as I was making big batches 35-45 gal at a time a full wheel barrow I added about 3-4 lbs of 10-10-10 to every batch and 3-4 lbs of lime. the trees have started to leaf out and put on growth so now they are on a liquid MG all purpose regimen weekly
Sal


 o
RE: Consequences and benefits of over fertilization.

Yes Al that was a compliment. ; )
I notice while i may not do the exact things you mention i do pretty similar with good results such as fert with a week solution often, watering till it drains out, root pruning,etc, etc, with my fig trees things i have been doing for years with my fig plants.
I did learn something new about the disk shape in root pruning and enjoyed that post and will start to try that shaping of root system on plants that will need root pruning next dormant season. Aside from my large container plants the rest now will be a smaller version for ease of back pain and management of them overall. Im not getting any younger .
Martin


 o
RE: Consequences and benefits of over fertilization.

  • Posted by tapla z5b-6a MI (My Page) on
    Sat, Apr 17, 10 at 12:12

Thanks, Sal. You're very kind.

Just so we're clear ..... you CAN grow healthy plants using fertilizers in the 1:1:1 ratio, even if it might not be the ideal ratio. Plants do take what they need from what's available and leave the rest, but what they do not use remains in the soil solution and elevates the level of solutes dissolved in it. Since they cannot use the 'extra', the level of electrical conductivity (EC) and total dissolved solids (TDS) is always higher than necessary. This in itself may be a minor issue or a major issue, depending on how frequently you fertilize and at what strength. We know for certain that using fertilizers with ratios apart from the ratio in which plants use nutrients reduces our margin for error on more than one front when it comes to nutritional supplementation.

I'm not making the case that it's the end of the world if you use a 1:1:1 ratio fertilizer by any means. Lots of people use 20-20-20, but not many can tell you WHY they use it. I simply wanted to explain that there are other approaches that are better choices.

I'm glad to see that many of us already realized the value in matching the ratio to actual usage, and those that didn't understand at least now have the information they can choose to accept or reject as they decide.

Ahhhh - I'm glad you mentioned the smaller container size, Martin. If I didn't mention it too, I should have. Those that keep potting up year after year will find themselves with 200 lbs of roots in a 50 gallon container after a few years, while those of us familiar with root work can enjoy a healthier tree of the same size in a container and soil volume a fraction of the size.

I think it's a good thing to entertain your opinions with some measure of doubt. I wouldn't want anyone to believe anything dogmatically, not even my own assertions; but some doubt for the sake of doubt, and follow others around with the express purpose of diminishing them. Fortunately, 99% of the people we have intercourse with on these forums are not that way. ;o) When we do wish to disagree, we would be much the wiser to comprehend fully what we are disagreeing with, lest our protests go unheeded for the demonstrated lack of understanding. We all learn soo much more that way.

Thanks again, for your kind comments.

Al



 o
RE: Consequences and benefits of over fertilization.

  • Posted by chills Zone 6b Mi (My Page) on
    Sat, Apr 17, 10 at 22:46

Al, I appreciate and will one day take you up on that offer. At this point, however, all of my figs have leafed out and I too am watching the weather carefully.

~Chills


 o
RE: Consequences and benefits of over fertilization.

My intent is to grow all of my fig trees in the ground as mother nature intended for them to be grown. That is not to say I don't have some trees in containers. My container trees now get a dose of a slow release fertilizer EARLY in the season, followed by a soluble type fertilizer LATER in the season if needed. My container figs are the spares for my in ground trees and some of them are waiting for a ground spot to be planted. I really don't care if my trees do fruit for me while they are in their containers. However, my in ground trees are very important to my research work. I want them to fruit ASAP and I pay close attention to their needs. My older in ground trees get fertilized with either 8-8-8 or 13-13-13....doesn't really matter to me as I adjust the dosage rate accordingly. I get excellent results with either fertilizer. No problems whatsoever with EC (electric conductivity) or TDS (total dissolved solids).

Last year and the previous year , I experimented with quite a few new fig trees. I planted new starts directly in the ground as soon as they were hardened off to full sunlight and heavy moisture. I pushed those trees hard initially with a regimen of 8-8-8 and later with a soluble fertilizer to get good growth on those new trees. They were weened from BOTH fertilizer and regular WATERINGS in late summer in order to prepare them for dormancy. You do not want any fertilizer or water induced rapid green growth on any young trees just before winter and exposure to cold temperatures. The results of my early planting experiments were some very nice trees....with some fruiting very quickly. In my zone I see no advantage to growing new starts in a container for a year or two before planting directly in the ground. On the contrary, there is a definite advantage to planting new starts ASAP in the ground.

When fertilizing fig trees correct DOSAGE and growing cycle TIME of application are very important parameters too. It is not just about nutrient ratios. (When I get a chance, I will respond more in depth directly to some baloney posted about this in another thread.) I use both 8-8-8 and 13-13-13 fertilizer on my in ground fig trees. Fig trees growing in a fertile soil simply do not need much fertilizer. Fig trees growing in a STERILE soil/mix always need fertilizer. Young in ground fig trees need more WATER than they need fertilizer in the first couple of years of their life. It is very VERY important to not ever allow the ground around a young fig tree to ever go completely dry at any time during the first couple of years of its life. Fig trees DO NOT HAVE TAP ROOTS because they were cloned from cuttings. Fig trees grown from SEEDS have tap roots.....however, those that were cloned (almost all figs trees) do not have tap roots. The feeder roots of a fig tree lie just beneath the surface of the soil.......and can be easily damaged by dry soils. By keeping the top soil layer around a fig tree always moist, you will see nice vigorous leaf and branch growth above ground because the developing root system below ground does not get damaged as long as the ground remains damp. After a couple of years of keeping the ground around a fig tree ALWAYS moist, a strong and more massive root system will develop that is much less prone to damage from drought conditions. Fig trees with good root system thus developed are far less likely to drop their fruit during dry periods......Celeste for example.

I manage my fertilizer dosages by LOOKING AT MY FIG TREES. If my trees do not grow at least a foot or two each year....they are telling me that they need fertilizer. I apply a small amount of a 1:1:1 type fertilizer directly on the ground beneath the tree then water it in with a hose. As stated before, I use either 8-8-8 or 13-13-13. I keep the ground always moist around the tree and observe how the tree responds to this application. If I do not see any rapid new growth on my fig tree after two to there weeks....I apply another small amount of fertilizer directly on the ground under the tree and sprinkle it with water from a hose....again always keeping the ground DAMP. I continue doing this until I DO SEE THE TREE RESPONDING......then stop with the fertilizer.

TIMING of fertilizer application is important to many fruit trees. Some fruit trees will simply drop their fruit if they are fertilized at the wrong time. I am experimenting with my fig trees to try to understand the effects of this parameter on optimum tree growth and fruit drop.

Dan


 o
RE: Consequences and benefits of over fertilization.

  • Posted by tapla z5b-6a MI (My Page) on
    Sun, Apr 18, 10 at 21:03

OK, Chills. I'll look forward to it. Mark your calendar for next spring ..... and don't forget.

Semper Fig! ;o)

Al


 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!


Return to the Fig Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.


Learn more about in-text links on this page here