Is collecting rain water really an option in phoenix?

No! It only rains during monsoon season in late summer. Houses don't even have gutters or down spouts for rain barrels.

Well then if no rain, your out of luck.

In other words, that FP is probably only around until the next watering. I can see why some people use a granular fertilizer in addition to FP. Not much I can do about my water source. As Steve indicated, can't rely on rain here. Our last rainfall over 1 month ago broke a 3+ month dryspell. So perhaps I will just learn to love burned tips. The tree appears happy otherwise. I even saw numerous flower buds in development yesterday.

Out of curiosity why not consider finding a good granular fertilizer if you're going to water via drip system?

@bonsai, I'm moving in that direction. I adopted FP a little while back because many people here love it and it seems difficult to find a granular fertilizer that has an equally good ratio of macro nutrients plus all the micros that FP has. I don't see anything at my local garden center that seems to measure up.

Silica hit that right on the nose my friend!!

That's the reason I use rain water for the most part when I can. It makes my plants look sickly using just tap over time. I even loose leaves to my citrus over time all winter if I don't use rain water. Thank God I have gallons upon gallons full.

I would buy distilled water and use a gallon or two to flush the soil at least once every couple of months. But that's just me Travis)

Travis, don't you have hose?

If you are using a very good porous mix, then you shouldn't have any deposit issues from water at all, if you water copiously. In fact, all you have to do is fertilize more when you do. And , at times I use Osmocote Plus as an extra back up in the mix to help with the lack of nutrients when so much watering is in use.

Travis, I only use 1/4 teaspoon per gallon a week, that's it even in summer. I might up it to a teaspoon if I notice they need more.

Osmocote Plus (15-9-12) is very close to FP in formulation and only lacks Ca with the micros. FWIW, I only use Osmocote for any woody containerized plants (regardless of species) and the FP for any non-woody containers or indoor plants. Once a season and done!

btw, if you are using the FP more than once a week, 1tsp/gallon is too strong a solution. Cut that back to a maximum of 1/2 tsp and you should see no more tip burn.

As noted, any liquid fert will flush pretty fast with water, unfortunately.

Any fertilizer with urea will take time to process to usable nitrogen via the bacteria in the soil (it varies by the temperature and whatnot, but call it 3 days total). Anything that gets flushed is...well, technically useless, but that's also only the nitrogen. The phosphorus and potassium will bind (and leach, but only slowly), and everything else will either be used, or bind and leach slowly, or wash out at variable speeds (boron goes fast; copper is practically eternal).

As Meyermike noted, Osmocote or the like can be used...but it's got a polymer (a plastic) coating. It doesn't sound like anybody here's trying for organic gardening, but please be aware of that. I don't use it for that reason; plastic polymers eventually end up in the oceans and I'd rather avoid that. Even yours in Phoenix.

Sulfur-coated urea is another option; it's a slow-release urea. I avoid polymer-coated urea for the same reason, of course. :-)

It may be a wee bit more complicated than buying a box off the shelf, but...mixing a 16-8-12 ratio wouldn't be that difficult using, say, sulfur-coated urea, monoammonium phosphate (immediately available nitrogen and phosphorus), and potassium sulfate (immediately available gentle potassium). And it's usually cheaper overall.

I've made my own fertilizer for ages, except I usually just use flat urea because I have no leaching concerns.

Lots of great comments here, thanks all!
@Mike, you said 1/4 tablespoon, did you mean teaspoon? FP instructions are in teaspoons so that's what I think in. It's 3 teaspoons to a tablespoon, so 1/4 tablespoon would be a little less than 1 teaspoon/gallon per week. Upping it to 1 tablespoon if they need more would be quite the jump. I trust your advice so I want to make sure I'm understanding ;). Also, I do periodically flush with distilled water, just to help.
@Gardengal, how do you supply the Ca and micros when you use Osmocote? That's been my big hangup with their more recent "Plus" reformulation. Since these are in containers and flush frequently, I am trying to keep the feeding as simple as possible (as it will have to be applied more frequently). I thought by flushing at each watering I wouldn't get in trouble with 1 tsp a couple times per week, but that was obviously wrong.
@morpheuspa, that is impressive! I'll know I've finally made it when I can make my own fertilizer! The nitrogen in FP is not urea based so I don't think it would get flushed before it's become available to the mix/roots, but it sounds like it won't stick around through the next watering.
All in all, I think my take-aways are that once a week FP will be insufficient when watering multiple times, and 1 tsp/gallon is a max weekly amount, and I'm probably better off aiming a bit under that for individual doses.

What is the nitrogen source? It may not be a great concern in terms of flushing (if I don't know offhand, I'll go do the research for you).

Making fertilizer is easy; I just gave you the formula. :-) But as an N source, you can choose anything that doesn't wash out easily. I like to avoid polymer-coated sources for that "polymer" reason, but any organic source that won't wash easily is fine, or, sulfur-coated urea as noted. At home, I add a bit of kelp powder and a touch of ferrous sulfate to the mix as well, but I know my home soils.

Most plant-available nitrogen sources will wash (in two of three sources) and wash somewhat in the third. Locked sources aren't plant-available much or at all, but there are exceptions (even flat urea, washable but unavailable, is technically slightly available per radioactive testing). The situation is...not simple.

For minors, you can add tiny amounts of additional things, but it's not really necessary for the most part. For calcium, a pinch of calcitic limestone (by preference humate-bound for fast release) will do, once a month to once every three months, depending on how fast your pH is drifting and calcium:magnesium balance in the soil stands. The bag should last you quite a while, it's made to adjust 5,000 square feet of soil to six inches about 0.5 points of pH (with an EC of 10).

Magnesium shouldn't be necessary. The tiniest pinch of Epsom salts once a year...maybe, but even that's likely overkill. As far as the other things, if you look on the boxes, the amounts listed are unbelievably tiny.

Calcium does not flush easily from pots; it's strongly soil-binding.

Note that soil testing is necessary to know what the soil pH is (every hand-held and home soil test is, frankly, awful). Even if it were perfect in terms of pH (most "excellent" tests have a window of 0.2 which, on a logarithmic scale, absolutely sucks--it's a factor of half again) it says nothing about the calcium:magnesium:potassium:sodium:hydrogen balance in the soil.

So again, blind additions of calcium...maybe not a great idea, but of the Bad Ideas, it's one of the least bad in that at least it causes some of the fewest problems. It just interferes with the absorption of phosphorus, potassium, magnesium, nitrogen, boron, manganese...

While citrus trees are peculiarly sensitive to manganese and boron shortages, it's incredibly hard to adjust those in pots. In this particular instance, manganese sulfate and borax (simple 20 Mule Team Borax would be the easiest) or boric acid (the pharmacy) would be the easiest sources (I'd use the borax, boric acid can present difficulties and you can use the other 99.99% of the box in the laundry).

You'd literally want to add 1 gram of each (1/28th of an ounce) to your fertigation system about twice a year--and I'd frankly be hesitant to do so without a soil test that specifically told me that boron was under 1 PPM and manganese under 3 PPM.

A better solution would be to use a solid organic feeding that will rot away and add these things in tiny amounts naturally--the reason I suggest these things for outside pots in the first place rather than the synthetics. Plus soil replacement when you refresh your pots will do this.

One final warning--you noted you had browning tips. If you have softened water, which is pretty common in arid areas, bypass it if you can when watering your gardens and trees. It's cheaper, true, but also note the word "sodium" under pH above. Sodium kicks pH way up, is useless except in the tiniest amounts, and causes leaf burn when it builds up--and it's very strongly soil binding. Sodic soils don't grow plants.

If that's been a problem, there are ways to fix it.

@Travis. FoliagePro is used by the teaspoon not Tablespoon. I use it weakly when watering. You will kill the plants if you use that much. I am sure they mis-spoke.

morpheuspa, how does the Osmacote plastic polymers end up in the oceans?

That is a good question Vladimir, I don't think plastic polymer fertilizers would be a problem when even growing in California.

Lastly, when irrigating with higher salt fertilizers, if nothing else, you can reduce the damage from the salts, by being sure that you do not let the medium dray out or nearing a dry condition.

"morpheuspa, how does the Osmacote plastic polymers end up in the oceans?"

"That is a good question Vladimir, I don't think plastic polymer fertilizers would be a problem when even growing in California."

Google will go into far more detail than I did with filtration and whatnot. Given the instant dismissiveness, it doesn't seem to be worth my time overmuch. Suffice to say the soil doesn't trap the plastic well and the lack of filtration is significant enough to be concerning in a household that already limits plastics use.

Plastics break down over time into smaller bits. Most notably, in sunlight...which is kind of what our plants really like to get... Tiny bits will, eventually, or when you change out the soils, end up in any number of places from the landfill to your garden. They'll wash out in excess watering. Those piles post-removal, when wet, they'll dump bits of plastic everywhere. Given enough time, that works its way down into runoff (remember, plastic doesn't rot reliably yet*) and into the storm drains.

Even Phoenix and California have them and they get used occasionally, and from there the water enters the...I'm presuming Rio Grande and whatever river serves the local storm drains to you in CA, without filtration as ours dumps directly into our local river.

And from thence, to the ocean. It's kind of the dumping grounds of the human species.

But hey, that Osmocote was cheap, wasn't it, and so much easier than actually making something at home.

* Some varieties have had recent species of bacteria evolve that actually will, inefficiently so far, reduce them to smaller polymers. Stay tuned.

@morpheuspa, I'll save this thread for future reference, thanks for the detailed info!
@Silica, I've actually wondered about that a bit lately because I know the salts are harmless when dissolved, it's only when they are left behind that they burn. My mix is very fast, for the Meyer it doesn't even have peat, just lots of bark fines and perlite. Still, I seemed to have overwatering problems in the past so I dialed the frequency back. I have a hard time judging when to water because of how loose it is. I can tell the mix retains water based on color and temperature, but I am never sure how dry I am supposed to let a fast draining mix like this get. So it's quite possible I have let it get too dry such that even prescribed amounts of FP have caused burning.

Thanks for the expanded name, Patti. "There is no urea nitrogen, which can easily burn delicate foliage and roots. Foliage-Pro contains both the ammoniacal and nitrate forms of nitrogen to insure healthy foliage and roots."

One, the statement is amusing. But we'll let that pass. Suffice to say that all forms listed can burn at high concentration and much of this is probably good ol' ammonium nitrate.

I did promise to tell you the stickiness in soils of each form if I could find it.

Nitrate Nitrogen (NO3-): We don't have easy subscripting here so botheration and all that. This doesn't easily bind to soils and makes up a bit over two-thirds of the nitrogen in FP. It washes right through just as easily as urea does (which is slightly less easily than you might think). Once in the soil, nitrogen cycling via bacteria can easily transform it into other forms of nitrogen like ammoniacal.

Ammoniacal Nitrogen (NH4+): It will stick to soils pretty easily initially; over the course of time and pH dependent, nitrogen cycling can transform it into nitrate nitrogen. Higher pH soils are going to have a lower affinity to allowing this to stick, again, an argument for not overdoing the calcium/magnesium blindly.

"@Silica, I've actually wondered about that a bit lately because I know the salts are harmless when dissolved"

Huge disagreement here; salts aren't harmless when dissolved. In high concentration (and measurements of this stuff in tablespoons is pretty high), they can burn even in fair amounts of water. If, as I assume, they're using ammonium nitrate, that really isn't weak stuff. Their claims of non-burning are dubious at best.

Case in point, that bit of sodium in the softener is soil binding. Over time it does build up, damage your soil, and render it incompatible with plant life. It's not that it's going to do damage when the soil dries, it's that it's impacting what your plant's roots can absorb from the soil solution even if it's completely saturated (and it can throw the soil pH higher than 8.0 over time). Yes, we actually do see soils like that in testing. They're usually...not good. That's a case of a small amount of salt adding up over time.

You can burn your own mouth with a hypertonic sodium solution as well. Ask my father about that one because he didn't listen to the dentist. :-)

Always respect a salt.

Was meant to say 'teaspoon, on my part. I will go back and correct.

Travis, thanks for knowing what I meant)

Thanks for the clarification Mike!

morpheuspa, PLEASE you need to read more carefully. I DID NOT write that dissolved salts were totally harmless. What I wrote was . "you can reduce the damage from the salts". Hopefully you will be more careful in future posts.

"morpheuspa, PLEASE you need to read more carefully. I DID NOT write that dissolved salts were totally harmless. What I wrote was . "you can reduce the damage from the salts". Hopefully you will be more careful in future posts."

Travis said that, not you. PLEASE you need to read more carefully. I hope you'll be more careful in your accusations in future posts.

ETA: Here's the expanded quote, which I trust lays to rest any additional questions you may have. Good day to you.

"@morpheuspa, I'll save this thread for future reference, thanks for the detailed info!
@Silica, I've actually wondered about that a bit lately because I know the salts are harmless when dissolved, it's only when they are left behind that they burn. My mix is very fast, for the Meyer it doesn't even have peat..."

I should have been more careful with my phrasing, as I was speaking generally and for a specific context, which was in relation to burning the roots (OP). In practice (with the amounts/concentrations I'm dealing with), the risk for burning is when the mix dries out and leaves solids. I'm not applying tablespoons of this stuff (which probably could create a hypertonic solution). It was between 1/2 and 1 teaspoon per gallon, which is within recommended specs, that I was questioning. Silica's comment reminded me that I had read elsewhere that salts generally burn when they get left behind, and that is what I was speaking to. I am aware that the concentration of dissolved solids will impact what the roots can absorb, but that wasn't what I was addressing. I'm also aware that salts can build up in a mix, which is partly why I flush at every watering, knowing how hard my water supply is.
I did not mean to start a row, and I recognize my imprecision/assumptions contributed to this.

Travis, this isn't your fault. Silica was, simply put, wrong.

Silica can retract his or her accusation, apologize for being wrong, or allow it to stand. Whatever.

Salt concentrations aren't exactly a simple science, it depends on the salt, and no blanket statement made about a salt and a concentration is going to be correct anyway as anything other than a very sweeping generalization. 200 mg in 1 liter of water of potassium cyanide is deadly. :-) 200 mg in 1 liter of water of sodium chloride is not all that easy to detect and you probably wouldn't notice.

Those are extremes, but even in plants, salts can be very gentle, like most sulfates, harsh, like chlorides, and so on. There's a salt index for how problematic a salt may be, but it's not comprehensive.

Some ions (the positive ones, mostly; the ones on the right-hand side of the equations or the right-hand sides of the sub-equations) bind to soils and can build up that way. Those usually influence pH one way or the other, and enter soil solution. So the situation is even more complicated than one might think.

Confusion is not only understandable, it's almost required.

I can tell you from experience. My water sucks.
If just for a couple of times I spray the roots to my orchids with it the roots take a down turn. I can't water my air plants and carnivorous plants with it either.

I can’t even use it in my humidifiers, it ruins those within weeks

And my fish tank forget it. You should see the salt crust I have to take off the tank after a month.
The other chemicals in my tap besides salt residue just cause so much damage on my trees before winters end. If I water my gardenias with it they croak in a short period of time. Thank God for the rain storms I get all summer.
Travis , if you can use distilled or rain water more often I would and if you use the emitters , then once a month at the least flush with fresh tap or rain water. As long as you flush the soil. Don’t forget hard water combined with fertilizers can wreak havoc.

Travis, don't forget that your mix has an advantage. It should not hold the stuff you fear as much as someone that uses a very peaty mix. Peat acts like a sponge, filter while they will just drain out better in a porous mix. You should feel good about that)

The tips getting like that are probably due to some other factor and will correct itself since others are just fine. They will get nice a green again right to the end)
Good night friend.

Thanks Mike, always so encouraging! I can't imagine being able to water a garden like yours with mostly rain water! Phoenix accumulated something like 3" in 2020, which is significantly less than our usually "lush" 8"! I do set out buckets for every storm but generally only collect 10-15 gallons every 6 months or so. My trees enjoy it for a week 😉. I can't use tap water because we have a water softener, so it's straight from the hose and a flush of distilled water every month or so. What I need is a good r/o system for outside....

Have you ever had a water analysis or does your city send one? I'm fortunate to have the third-softest water in the nation naturally (the first is Portland, Maine). There are about twenty ties for third, we get ours from natural and artificial lakes in the Poconos.

Fortunately, most hard water is hard due to calcium. It causes a lot of buildup, and soap scum (the sodium in soap get substituted on the fly with the calcium from the water as your water spontaneously gets softened a little), but the plants don't care much.

Sometimes it's magnesium, which is much more of a problem. And sometimes it's other elements (trivalent or divalent metals, usually), and that can be major issues for plants (you don't notice it in many cases, or it'll be removed at the water treatment plants as some of those are toxic). Excess iron in water leaves tons of stains and just tastes awful...but it's far more common in older pipes and metal fixtures.

Washing soda (sodium carbonate) is more effective in the washer and for cleaning than baking soda (sodium bicarbonate), but if you use it for cleaning, wear gloves. It has a much higher pH when concentrated. I'd recommend just using baking soda. I make my own laundry soap (and all soaps, actually) and use an admix of washing soda in the formula to increase cleansing. Even in very soft water, it does help remove dirt.

Fun fact: To easily remove soap scum, pre-soak with hot water and baking soda, let sit for 5 minutes. Cover with a towel, then soak the towel with vinegar. You'll need to do a bit of scrubbing, but the scum will be much easier to remove after that.

Sorry, don't get me started on water, soap, ions, soils...it's all related... :-)

Travis, how is it going these days? I almost e-mail you but then I al also wondering how your trees are doing my friend??

MIke

Hi Mike! Long time, no chat! I am doing well, how are you? My Meyer is looking good, has kept 7-8 lemons so far. Last year it didn't keep any, so I am hoping these ones will survive the summer and make it to harvest. My grapefruit is giving me grief. I'm planning to make a post about it in the near future. It lost several leaves from a watering incident a few months ago and now I'm wondering about pruning strategies to balance the growth. It flowered for the first time this spring but didn't keep any fruit. Maybe next year. I might swap it out. I don't know. I assume your trees have made it outside by now? Your garden is probably a garden of Eden right now!

Here's one of the lemons on my Meyer.

Travis, well I'll be) Look at that. You must have favorable weather lately, because what it does here affects there. I am happy for you. That darn grapefruit tree though, right? Soo good to know things are ok with you. Same here.

It's been nothing but raining here, something we have needed desperately . For the first time over an inch of rain in ten years at once. I have had over 3 in the past 3 days. Not a day of sun for the past 4 and COLD!!! Yup, still. It was high 80's last weekend and summer like which made everything grow earlier!! All my ground plants are a month ahead of schedule. Strange. Now all this very cold air only 40's for 4 days and cold rain to water everything and grow like monsters! I never had plants grow like weeds before, twice the size. The cold is not hampering my citrus trees either, thank God.

I will post a couple of updates for you my friend. I am wearing a coat today , in fact for the past few days, then by Wednesday shorts and hot.,lol

Congrats on that fruit!!

Mike

I'm glad to hear your garden is rejoicing in rain! It's been months since we've had any here. We're approaching our monsoon season which has been a real dud for the last two years. Weather service says it's about 50-50 we have a great season or another drought. I'm sorry it's cold for you though. We definitely don't have that problem! We're hitting our triple digits consistently now.

Travis, I suppose if I had to choose between triple digits or cold, I will take cold. Ha. That is hot and I think trees suffer more in extreme heat verses a few colder than normal days. Thank God that cold has left and today feels much warmer. Very cloudy but at least above 70. 90's by the weekend for days which is very early for us. It's been an odd year here too. I hope you get that much needed rain. You would be surprised at how our trees respond to good ole rain verses tap water. Thanks. I will share photos soon.