I used identical soil - a modified 5-1-1 - in all five containers. I modified it because I had a lot of good homemade compost to use, and for budget reasons couldn't fill 5 half-barrels with true 5-1-1. Actual soil is: 15% peat moss, 30% redwood bark (as close as I could get to fines, by screening), 23% screened compost, 12% play sand, and 20% perlite. I added some slow-release fertilizer and some dolomitic lime.

They are all watered via drip and have the same schedule and same volumes. The drip system was off for most of the winter. They all get the same amount of sun - as full as it gets on my property. I've inspected them carefully for insects (day and night), and can't find anything out of the ordinary.

From day one, the avocados appeared unhealthy, with leaf tips browning almost immediately, and leaves curling. I assumed I had over-fertilized and did a few heavy watering sessions and then let them dry out for a week, then resumed normal drip. The citrus (one of them included below) are amazingly healthy and growing like crazy. I left everything alone over the winter, but the avocados have not recovered, and are dropping leaves. New shoots appear and then brown off as well.

I have to assume it's root rot, even though the citrus are happy as clams in the same conditions. What are my options - is it too late to save the avocados? If I repot them, should I try to prune any damaged roots? How can I amend/improve the drainage of the soil enough to prevent the issue - ideally without buying an entire new batch of ingredients for mix?

Thanks!!

Edit: I know I need to remove the stakes. I will be doing that this Spring, but I wanted to repot first if necessary.

Sick avocado #1:

Healthy citrus:

Sick avocado #1 leaves:

Sick avocado #1 new growth:

Sick avocado #2:

Sick avocado #2 leaves:

Sick avocado #2 new growth:

Assuming you used the actual bark PIECES and not the smaller fine particles you screened, then your mix is at 50% bulk, vs. 85% in actual 5:1:1. Then, throw in compost (screened to use the chunks or screened to get the chunks out?), peat and SAND -- and you have considerable heftiness in the "soil" portion of things, it seems like.

Without knowing what you actually did or didn't do, specifically -- I'd guess between the really dense soil + overfertilizing + overwatering (to remove over-fertilization, haha) has really affected the tree.

If this were my tree, I'd remove it from the current soil, check the roots to verify it is indeed soaking, sopping wet and probably rotting -- trim cleanly, and repot in actual 5:1:1 mix, water well ONCE and leave it be for a couple of weeks to see what happens. It's not too hot yet here in Northern Cali (though not sure about where you are, specifically) so letting it settle in for that period should be fine, I'd guess.

To give you an idea of what 5:1:1 looks like prepared according to Al's recipe, here is one I made up a couple of days ago:

THIS PLANT WAS NOT MULCHED. You can see there is BARELY any soil in this, though what is there does retain water nicely; water drains out of this really fast while the soil does retain moisture after a watering. I'd "guess" that the soil you have right now for your tree does NOT look this "bark-y" (assuming the bark you have on top is mulch?)-- and the addition of the finer elements you added would further bog down the water.

Can't help much with the actual avocado likes and dislikes; I had one tree in the ground that was no less than 20 years old when I bought the house, and I fertilized that tree maybe twice a year and it thrived on what it received from the sprinklers only -- and I had one that I sprouted from a seed. :-) Not quite the same thing, so I don't know what other suggestions to make.

Someone will more avocado-specific knowledge will come along, I'm sure.

Hope you can rescue the trees; they look like they should have been beautiful! In fact, they look like what I have done to gardenias 2.8 billion times in the past, haha.

-Grace.

Thanks very much for your response! This was my first attempt at making a "non-bagged" potting soil, and I likely got it badly wrong.

The citrus all seem to love it, though.

I had the hardest time finding what Al calls "pine bark fines" - they don't sell anything matching that description that I can find near me (San Jose, CA), unless you are ordering by the ton. Also, the only source I could find for perlite (2 cf bags at HD) were VERY expensive, considering the volume of pots I was filling, and I couldn't stomach the cost.

Finally, I did intentionally up the standing water capability after reading about some forum posters who needed to water pots several times a day (!), and I added the compost despite Al's distaste for the stuff because A) I had a lot on hand, and B) I wanted to provide nutrients and microflora without having to micromanage the soil.

Clearly I overdid it. Do you have any suggestions for sources of reasonably-sized bark in the Bay Area?

Thanks!

Totally understand. Trying a soil that is....not "soil" is unnerving! I just started making "gritty mix" and I was a ball of nerves, lol.

Absolutely, I have a place. In my area (Peninsula), Lyngso in Redwood City is the best. I got enough bark, quartz and pricey pebbles to make gritty mix for both of your planters for $17 and change. Since you're doing the 5:1:1, just the bark would cost considerably less; I opted for some very pretty stones that cost entirely too much compared to the other pieces.

Perlite, as it's only one part, should be more than enough with 2 cu. ft. (or much less). Same for sphagnum peat moss. Garden lime, you can buy at OSH in small sizes for about $9--probably enough to make 100 half wine barrels.

And that's it.

Re: your citrus trees, at first glance they appear healthier compared to the avocados, but if you look closely, the leaves in the lower half are completely yellowing. This could be a result for many things (nitrogen deficiency?), I suppose, but it's also one of the first signs when a plant is drowning....just a heads up. Left alone, I think it's on the same path, unfortunately.

As for watering, in my area (SF-SFO), I'd never think you would need to do more than one full watering every other day and daily during one of our 85 degree + heat wave days. In the east bay or hotter areas, I think you'd probably need to water daily, period, during the hottest months. Now gritty mix -- I could see one potentially needing to do more than once to be good for the plant in really hot areas if the plant is really sensitive to heat/drought. (Gardenias? Haha.) Given that my natural tendency is to overwater, this works for me but it may not be for you?

If not, then I think Al suggests replacing one part bark with another part peat (or maybe just potting soil) to increase retention. With the plants I have in 5:1:1, I upped the peat only by making it 5:1.2:1 (I live dangerously lol) but its very NICELY moist, and not "soaked".

In any case, while I can't speak to avocado trees specifically, I would definitely remove all four trees, wash off all the roots to bareroot and repot all four trees to start with a clean slate. I would also prune back the tree a little but others may disagree; I tend to repot when I feel like it. Don't fertilize it for awhile either -- just clean soil and water thoroughly once -- and a week later when completely dry, reassess.

Oh. One other thing: I don't know that I'd use a drip system for 5:1:1. It beats not being watered, but unless there have been major advancements in drips since I last used them in 2006, this soil simply doesn't absorb and transfer moisture like regular potting soil (dense) would. There's so much space and aeration between chunk/bulk pieces that if a drip drips water into one area, it really doesn't mean the water will flow/absorb into the other parts of the soil. DEFINITELY for me anyway, this is a hand watering or at worst, sprinkler type soil--not drip. A garden hose fully showering each planter shown for 45 seconds, I'd guess, would be ideal for summer days, to ensure each piece of bark and perlite is as soaked as can possibly be. I don't know if this is a deal breaker for you.

Good luck! Hopefully, someone with more avocado experience contributes!

Awesome, that's a lot of great info, thanks again! Unfortunately, I'm trying very (very) hard to 100% automate the watering of my entire yard, pots included. This isn't just for my sake - I've killed too many plants from neglect in the past! I'd like to think that it's possible to strike a balance between water retention/distribution and drainage in a pot, even if it means repotting every few years due to compaction of the soil.

Unless anyone else has some suggestions, I think I'll follow your recommendations of bare-rooting the avocados (and gulp, the citrus... this is going to be expensive...) and making a sort of cross between 5-1-1 and potting soil. I hesitate to increase the peat, so maybe swapping 1 part of bark for 1 part of compost, sort of a 4-1-1-1? I could also try screening the existing mix and only keeping the larger particles, then amending that with bark and more perlite.

How did people grow things in containers before the Internet? The previous owners of my house had some nice large citrus in half-barrels, and I guarantee they've never heard of Al or his mixes...

If the cost is going to be prohibitive -- and firmly believing that gardening should not put one in the red -- I think your 4:1:1:1 you described above would be worth a shot. I would guess that trading out one part won't make or break anything. To my knowledge thus far, the objective is really to keep the larger particles at a significant maximum to provide the essential drainage throughout the medium.

Without knowing exactly what the issue with your current issue is, I would not sift the current soil. Especially with wet sand - - it would be labor-intensive and not very effective, I'd imagine.
Do you have any land you want to amend? :-D

Post photos if/when you do repot!

Avocados really resent root-disturbance, particularly bare-rooting...at least in my experience. After re-potting, I've found it especially important to protect the plants from intense sun/wind, and also to keep the medium evenly moist until the Avocado is fully established. I lost nearly all the leaves on my Avocado when I re-potted last, and I thought I was being very careful and doing everything right.

Did I read somewhere that you changed the mix propertions and ingredients because posters here said they had to water their 5-1-1 "everyday"? I'm curious who might have said that, since such a statement runs completely contrary to my experience and the experience of so many others who actually use these mixes.

I would recommend that you simply substitute the compost for the peat fraction in the 5-1-1. Also, did you add the Dolomitic Garden Lime? Due to GardenWeb's new format, a bank of advertisements obscures the better part of your first post and I can only read portions.

Josh

Good to know about the avocado sensitivity to root trouble - perhaps that's why they're so unhappy and the citrus aren't (yet), in the same soil. Do you still think it's a good idea to bare-root and trim off the rotted roots? Any alternative to dealing with root rot?

I don't remember who mentioned the extra watering, but I did read extensively on these forums before going with my soil choice. There was a lot of discussion about the hottest summer months requiring once or twice daily waterings of plants in such mixes (5-1-1 or gritty, I don't remember which, or both).

-keodark

Small volumes of most mixes will dry out during the Summer months...but a properly-sized container with a correctly-watered 5-1-1 should not need daily watering. I wondered who might have posted that idea because this Forum has been plagued by folks who criticized the mix without actually having used it. Unfortunately, many read an offhand comment like "...I can't be watering my plants everyday in that mix" - and this notion has spread, however unfounded.

I think it is essential that any rotted roots be removed, but I wouldn't bare-root completely. Minimize the trauma to the roots. I also suggest that you move the bamboo stake away from the trunk, closer to the edge of the container. Use two stakes, perhaps, tied to those outward branches. Move the tree into bright shade for two weeks of recovery - a rule of thumb I follow for trees with large leaves.

I lost a 20-year-old avocado tree after root pruning and replanting it in gritty mix two years ago. It had been sadly neglected over the years, rarely repotted and living in compacted soil with only a little fertilizer. And, it looked pretty good. Then, I joined GardenWeb and learned about the better soil mixes. The avocado was one of the first plants I moved to gritty mix. Since then, I've probably planted or repotted more than a hundred different kinds of plants using one of these mixes, and almost every single one is thriving (including my new 2-year old avocado tree).

After the first couple weeks, I don't really find that the plants need to be watered a lot more often than they were in store bought potting mix. It was only right after repotting that it seemed I needed to water every day in the summer outdoors. I have since learned to make sure the bark is thoroughly wet before adding the mix to the pot, which has solved the watering problem. Even during the heat wave last summer, I only needed to water my many container vegetables every other day. I think some of the people who complain about having to water so much are using containers that are way too small for the plants growing in them (like tomatoes in 5-gallon buckets).

Back to my avocado. I believe I was too aggressive when root pruning the plant, and the daytime temperatures were extremely high at the time. I assumed that it was a tough plant because of how well it had handled its hard luck life, but I was wrong. My avocado completely wilted right after I repotted it, and the leaves gradually died over the next couple weeks. I tried for weeks to keep it watered and sheltered hoping it would come back, but no luck. Finally I emptied the pot to look at the roots. There was no root rot or any sign of a problem. But I could tell that the roots had never grown after being repotted. In other words, my avocado was doomed before I put it in the gritty mix. It resented the root disturbance so much, it up and died on the spot.

Your avocado is still alive, so there is hope you can save it. If I were you, I wouldn't pull it out of its pot until it looks healthier. Although your potting mix is not the best, it's a lot better than what many people have used. If you baby the avocado and avoid overwatering it, it could pull through. If you uproot it again, it could bite the dust. I know some others may disagree with me on this.

Finally, I want to say that in my experience adding sand to a potting mix always leads to more compacted, less freely draining soil. I know it's been recommended for improving drainage for hundreds of years, but it has always been a disaster when I used it. I do add compost to my 5-1-1 when growing vegetables in big smart pots, but never more than about 15 percent. (It replaces the one part peat.) The 5-1-1 I use for plants growing in regular pots is pretty close to Al's original recipe and never contains compost or other organic nutrients.

Good luck with your avocado. My new one is doing very well in the gritty mix.