Hello all,

I have been a member of this forum for almost a year with no posts, so I guess it is about time to join the fun. I have been growing figs for over ten years and have really become a collector over the last few years or so. I have actively read posts over the last year because I am of the opinion (as I told one member) that when you come to the "grown ups table" you sit and listen and try to pick up on experience and expertise. You don't interrupt by asking blind questions with limited experience and observations. So I tried to do that. I bought cuttings and plants from quite a few of you. I do have a real question, though. I have heard a lot about the use of gardening lime for figs. I have witnessed the video with the layer of "snow" that the Bellaclare boys used. I know that it is effective (and native to most fig original growing zones) due to raising Mg and Ca levels, but what exactly does it do ( absorption of other minerals, allow more fruit buds, etc)? I just wasn't sure why it works. Can anyone help? Thanks, Bill

There are scientific explanations to this using chemical formulas, but in two words it is that fig roots cannot use the nutrients from an acid soil even when there is plenty of them in it. Lime is lowering the acidity of the soil and the nutrients become available to the roots. It is like with ocean water, there is plenty of it, but one cannot drink it before it is  desalinated.

Best regards and welcome

Hello Bill,
I agree with Boris' explanation and like his simile. I would like to add a document that explains in simple quasi-scientific terms the relationship between the Macronutrients (the group to which Calcium and Magnesium belong), Micronutrients, and Soil Microbes that are required for healthy plant growth. You also had hit on the main reason IMO, that a higher that "normal" calcium level is required by fig trees, they have adapted to it over time in their native environment and granular dolemite limestone is not as effective at drastically changing PH values as is often thought, but increases the calcium and magnesium levels. Hope that the document helps. Good luck.

 nutrientdeficiency.pdf    

Welcome!  Glad you found your voice. 

Welcome, glad you decided to take the plunge and post

Welcome to the forum,

Here is my attempt at a simple answer.  The lower the pH (this equals higher acidity) the more tightly the soil holds onto nutrients.  When you lime soil it raises the pH (decreases acidity) and loosens the grip of the soil on the nutrients.  This loosened grip allows for easier uptake of nutrients by plants.

James,
You're welcome.
Were the roots disturbed when the plant was repotted?. If they were or if they are root bound, that could explain some of your symptoms.

You did not post your actual potting mix ingredients, but I have had good success with 1 cup of Dolemite limestone to 5 gallons of 5-1-1 mix. If everything is good with the roots, I would just remove the top most mix, add limestone , mix together and replace the mix. I would then flood (flush) the pot with water to get the Limestone distributed.

no.. I don't think the roots were disturbed too much.. it was a while ago, so can't remember this particular one if it stayed together well during the transfer. Some thin roots out to the edge of old pot, but by no means root bound.

Now that I think about it, I used a different potting mix on this one. It was called Living Earth Rose Soil. (first on the page here http://livingearth.net/products-services/products/landscape-soil). The guy told me it should do well for figs too. After getting it home, I found it to be much heaver than I liked, so added about 60% perlite to lighten it up. It seemed to be pretty sandy. The rest of that bag, I mixed with Miracle Grow potting mix and perlite to lighten it up much more.

I think I'll pull it out of the bucket and try to get back down close to the original 2 gal root ball (careful with the roots). And re-pot it in new soil. I'll mix in a little bit of dolomite lime too.

welcome to the forum. 

Well, I repotted my MLS. Hopefully I haven't done it in. The pH was back to normal, but still looked unhappy. After getting it out of the bucket, the soil was very compacted and some black stuff growing in the bottom. Mold? The roots were starting to wrap around the bucket but we're very thin and not healthy looking. It seemed like they were trying to get away from the soil.

Washed the root ball down to about a 1.5 gal pot size and put back in 5 gal bucket with my good light mix.

I guess I'll see in a day or two how it's doing.

welcome to posting and good luck with the MLS

James,
Welcome! The pH of a media around the roots of an actively growing plant is normally more acidic (low pH) than the surface of the media. There are lots of problems with the probe type pH devices. For those reasons, it is best to test pH with what is called the pour thru method. You do not need an expensive pH meter. You can use pH strips which you can buy here:
http://www.coleparmer.com/Category/pH_Test_Strips_and_Indicators/17466
or try your local swimming pool/spa supply store. I suggest that in addition to a pH 0 - 14 strip you get a pH 5 -9 strip. Your cost is ~$0.20 per test with the strips. I am attaching a file on doing pour thru pH testing that I hope is helpful. An article with some discussion of how roots can impact media pH can be found here:
http://www.gpnmag.com/sites/default/files/Styer1.pdf

You can use dolomitic lime to raise the pH. Be aware that there is significant variation from one lime prep to the next. Its effect is gradual which makes it easy to overshoot if you are in a hurry. Big growers will test the amount of lime require to raise the pH of a media over 4 to 8 weeks prior to planting in it. It's sort of technical, but that is discussed here:
http://hortsci.ashspublications.org/content/42/5/1268.full.pdf+html

Hopefully your repotting solves your problem & this can be useful in helping to avoid repeat problems.

Good luck!

First I want to apologize to Bill for Hijacking his original thread..  I didn't mean too, it just got out of hand.  The repotting definitely stressed it out. A few of the lower leaves dried out.  But it's still putting out new growth at the top.   I think it's going to be fine.

Thanks for the info, DWD2!

I also find the advice about using Lime as strange. If you search on the internet sources claim that the optimal soil PH for figs is 6.0 to 6.5. This correct PH optimizes nutrient uptake into a plant.

Soil PH can also be changed if the PH of your water is higher or lower.

By example, In my area the Soil PH is about 6.5 and has adequate Calcium in it . My water has lots of Calcium and Magnesium in it and has a PH above 7.0. In contrast rain water has a PH of less than 7.0 because it has carbonic acid in it as it falls through the CO2 in the atmosphere.

So in my case my soil is has a PH of between 6.0 and 6.5 during the rainy season, but during the summer I have to water with alkaline water which raises my PH above 6.5.

So here is the question, why should someone like me use lime which would raise the soil PH above what is ideal for figs. Right now my PH is perfect in the winter and is too high in the summer? So if I add lime it will only make things worse.

And for that matter why should anyone add Lime unless the PH of their water and soil is below 6.0?

Figsation,
In answer to your question ... Container grown plants, in a peat based potting mix.

I also use Dolemite limestone in my gardens and get much larger healthier plants with, than without. I started experimenting with Dolemite limestone after reading about the Mittlieder Method of gardening and his pre-plant mix, it works.

Pete, In that case it would make sense because I think the PH of Peat alone is less than 5.0. So it needs to be raised up above 6.0.

More info on PH and Lime

Here are PH soil maps of the USA. High rainfall areas tend to have acidic soil with PH less than 6.0.

http://www.bonap.org/2008_Soil/SoilTypesRelatedMaps.html

Bellaclare  and most of East Coast falls into the low PH area so lime makes sense. For many in the arid West it doesn't seem to make sense.

This article on turf grass Lime application also explains the benefits of application in low PH situations.

http://www.uri.edu/ce/factsheets/sheets/lime.html

Figsation,
I think that there maybe some confusion between Calcium being supplied in Lime, Limestone, and Gypsum. Calcium is essential for plant growth. For high PH areas Gypsum is recommended, for Low PH areas Lime is recommended. There are different types of lime and limestone as mentioned in the section on Calcium in the PDF that I attached in post #3. It also notes that Calcium deficiency is rare, but if its not replenished (by added organic matter), it needs to be replaced (added).

Welcome.