Astrophytum asterias

[Steve Johnson]

SO many "experts" seem to think that all cacti should be grown in the same medium and watered in the same fashion and given the same bright light conditions. I have learned in the last couple of years that this is not so, and so solicit the opinions of the true experts here at this forum.

thanks for your input.

Glad to help however I can. And I totally agree with you here -- treating all cacti the same doesn't work out well, but if you develop a general rule and identify the exceptions that are appropriate to certain "difficult" species, you'll find they're not that difficult at all. This is really just a matter of gaining experience, and we're blessed to have online resources for advice which didn't exist when I first got into cacti almost 50 (50?!?) years ago. Speaking of...

How about this stuff... Nothing organic, readily available from Amazon...
https://www.amazon.com/Bonsai-Soil-Mix- ... +amendment

Or maybe this stuff with very little organic content?
https://www.amazon.com/Quarts-Bonsai-Su ... onsai+jack

The pine bark in the 2nd mix would be a deal-breaker for me. The 1st mix is better, although I'm not sure if the charcoal does anything for cacti (I don't think it would hurt, anyway). I'm a firm believer in keeping things simple, so IMO both mixes are needlessly complicated. (I could never figure out why some growers like to "over-engineer" their mixes.) Pumice is the ideal mineral due to its unique combination of open porosity and good water retention. Quite a few growers do well growing their cacti in pure pumice and nothing more. Whether or not that would work for you depends on:

1. Your climate. In desert-type conditions with constantly low humidity, straight pumice dries out too quickly, so a certain amount of soil is needed for better water retention. If you live in a fairly dry climate, you may need some soil in the mix.
2. Wind. Relatively speaking, pumice doesn't weigh much, and you don't want light pots tipping over in the wind (especially smaller ones). Don't know if that's an issue for you, but it certainly is for me -- the primary reason why I mix pumice with granite gravel to make the pots heavier.

We can find straight pumice online through Amazon and eBay, but I noticed that it seems to be a pretty expensive proposition for people who are keeping more than a few plants. Bonsai nurseries sell pumice, so if this is a problem for you, find out if you have a brick-and-mortar bonsai nursery within driving distance. If you do and they sell it, this'll be more cost-effective.

Don't want to veer too far off from your original reason for posting here, but if you visit my Member Topics thread, you may find a few cultivational items of interest in my end-of-summer review. They'll lead off Part 1 (which I'm still working on), and I hope to have it up by the end of the day. If any of them turn out to be useful, excellent.

[WayneByerly]

... but if you develop a general rule and identify the exceptions ...

The more cacti I run into, the more I seem to find more "exceptions". That general rule maybe only covers half the cactus that people normally collect ... the other half being the exceptions. There are SO many of them that almost fit the general rule, but have some smallquirk that causes them to require some special treatment.

... The pine bark in the 2nd mix would be a deal-breaker for me ... Pumice is the ideal mineral ... Whether or not that would work for you depends on:1. Your climate... 2. Wind ... I mix pumice with granite gravel to make the pots heavier ... find straight pumice online through Amazon ... this'll be more cost-effective.

I think, considering the delicate nature of the Astrophytum asterias, that you have talked me into using straight pumice. Or maybe straight pumice with some granite mixed into it (I don't need to worry about the wind as my "outside" cacti are in a "greenhouse" (sic)). Would chicken grit (which is just granite broken up into little tiny quarter inch pieces) be satisfactory? Both are readily available from Amazon. And here's why this is desirable. I'm currently 65 years old. Or will be in a few days. Some 22 years ago I was disabled in a motorcycle accident that left me unable to work. My health has done nothing but grow worse ever since. There have been days recently that make me seriously wonder whether I'll make it to my 66 birthday. Or maybe even my 65th. So being able to order the stuff online is ideal for me. Just about ALL of my "getting out" involves either going to the grocery store or the doctor. I don't do anything else. Sorry to dirty the water with my "personal problems", but the subject of "getting out" came up and I thought I should explain somewhat without going into too much detail.

My "climate" is:
35 degrees north latitude (zone 7), about 60 miles north of Chattanooga Tennessee. The greatest majority of my cactus/succulent collection resides outside in a greenhouse. A rather small and primitive greenhouse that I built myself. Something like 5 feet by 8 feet. It has a thermostatically controlled heater that comes on at 40 degrees and then goes back off at 45 degrees. This way they have a cold winter break without having to suffer through sub-freezing temperatures. In the summertime, I keep the flap/door open with a square box fan in it to keep the air circulating. I don't know what I can do about keeping the air circulating in the winter time, which worries me a little bit as the humidity here is higher than what one would find in American desert Southwest.

My Greenhouse:

Greenhouse shot (800x600).jpg (130.57 KiB) Viewed 2168 times

Don't want to veer too far off from your original reason for posting here, but if you visit my Member Topics thread ...

Those polanski have a profoundly substantial root system . I don't think i've ever seen anything like it . And I've been looking for a Mammillaria spinosissima that bright shade of red for quite some time. Even when I go to google, execute a search for that cactus, and then switch to "images" view, MOST of the pictures I see are not NEAR as red as yours is ... Having one THAT red would almost be "the crown jewel" of my collection. I've wanted one for a LONG time. It was almost the first cactus on my "I wish I had one of those" list. I'm quite jealous .

[WayneByerly]

Deleted as a duplicate

[WayneByerly]

Decided to go with pumice and montmorillonite clay (also known as turface), a fired clay soil amendment. I read somewhere that pumice has a somewhat alkaline property, and the monty clay is supposed to be acidic enough to help offset that alkalinity.

[Steve Johnson]

Decided to go with pumice and montmorillonite clay (also known as turface), a fired clay soil amendment. I read somewhere that pumice has a somewhat alkaline property, and the monty clay is supposed to be acidic enough to help offset that alkalinity.

The mix you're suggesting should work well, so go for it.

[WayneByerly]

As quick as the stuff I ordered arrives, and it shouldn't be but two days, I'll re-pot this Astro. Sometime in March I'll start looking for evidence of roots, and let y'all know how it turned out ... maybe in April.

[WayneByerly]

I made a post that said that I had elected to go with pumice and turface. but it is no longer here. Anybody ever experience having one (or more) of your posts disappear?

But nevermind ... that's not why I write. I write to ask, as long as I am going to use an entirely inorganic growing medium for my Astrophytum asterias, how can I feed it? I have some worm castings that I could make a "tea" from that I could use when I "water", and I have some Schultz 7-drops-per-quart 2-7-7 liquid fertilizer. Would either (or both) of those be satisfactory when trying to "feed" my A. asterias? And if so (or not) how oftern should I feed/fertilize?

Despite having had the A. asterias for four years, I don't think that has made me an expert. So i'm here NOW to solicit some basic tips/tricks/techniques in A. asterias care.

[Steve Johnson]

Only downside to going soil-less is that cacti have to be fertilized every time they're watered. My fert of choice is Dyna Gro All-Pro 7-7-7, in fact the only fert I'll use. We can get it only by the gallon, which means it's kinda expensive. If that's more than you're willing to pay for, Dyna Gro also makes a 7-9-5 in smaller quantities, by the quart (32 oz.)...

https://www.ebay.com/itm/Dyna-Gro-Grow- ... SwdGFYxwKC

...or in the 8-oz. size:

https://www.ebay.com/itm/Dyna-Gro-Grow- ... SwILFZsBf0

Dilute 1/2 teaspoon of the liquid concentrate per gallon of water. I've been acidifying my tap water with 5% white vinegar since 2012, and compared to what happens when we water our plants with hard water, acidification makes a big difference in their long-term growing quality. If you're able to store rainwater, use that, and you won't need to acidify.

[WayneByerly]

My fert of choice is Dyna Gro All-Pro 7-7-7 ... Dyna Gro also makes a 7-9-5 in smaller quantities ...

Thanks everso for the links.

Only downside to going soil-less is that cacti have to be fertilized every time they're watered.

I think I can live with that. I love 'fid-ling' with my cacti. I presume that watering schedules are still what they used to be ... wet it and then let it get dry before watering again? Or should it be something different because it's soil-less?

I've been acidifying my tap water with 5% white vinegar ...

I don't have tap water. What I mean by that is, I've got an indoor source of water ... but it just doesn't come from the city. All my 'tap' water comes from a well. So I don't know whether or not the pH of that water is what it should be. I tend to think that because rain water percolates down through the ground to an aquifer that the pH is very similar to what you would find in Rainwater. But as long as we're on the subject, to what pH do you acidify your water?

If you can store rainwater ...

(snort! ... snicker ) we just bought, within the last week or so, a 55 gallon plastic drum for just that purpose

[Steve Johnson]

I presume that watering schedules are still what they used to be ... wet it and then let it get dry before watering again? Or should it be something different because it's soil-less?

Exactly what I do with all desert cacti in the growing season -- deep watering, then let the mix dry out top to bottom between waterings. I water most of my cacti every 2 weeks in spring and summer (including the A. asterias). The exceptions are Discocactus, Melocactus, and Uebelmannia once a week, and I water the Turbs every 3-4 weeks in spring, then every 2-3 weeks in summer. (A number of Turbinicarpus species are prone to splitting if they're plumped up too much, so I'll let them get a bit thirsty between waterings.) Bear in mind that what I'm talking about applies only to my climate.

I've got an indoor source of water ... but it just doesn't come from the city. All my 'tap' water comes from a well. So I don't know whether or not the pH of that water is what it should be. I tend to think that because rain water percolates down through the ground to an aquifer that the pH is very similar to what you would find in Rainwater. But as long as we're on the subject, to what pH do you acidify your water?

Well water tends to be hard, so it would be helpful to know the pH of the water coming out of your well. I posted the following last year, and this is pretty much everything you need to know, including the answer to your question:

viewtopic.php?f=31&t=34730&p=323572#p323572

(snort! ... snicker ) we just bought, within the last week or so, a 55 gallon plastic drum for just that purpose

Hopefully your rainwater supply is consistent from year to year. California is a drought state (always has been), so mine certainly isn't. Since the only water supply I can rely on comes from the tap, you'll understand how important acidification has been to the good health and quality of my plants.

[WayneByerly]

Allright, update us if it makes it. They dont sell root hormone here, but i am intrigued by your success.

You advised me recently on my Astrophytum asterias. Part of your advice was a soilless growing medium which I agreed to. 50% turface and 50% pumice.

Trim the roots, put it in the medium and wait for spring. But my A. asterias is inside. It doesn't know anything about spring vs. winter and it is shriveling even more now.

Seeing as how this cactus is inside where it is warm with a good source of moving air. Should I not perhaps moisten the growing medium in an effort to promote root growth?

Help quickly please!

[ElieEstephane]

Allright, update us if it makes it. They dont sell root hormone here, but i am intrigued by your success.

You advised me recently on my Astrophytum asterias. Part of your advice was a soilless growing medium which I agreed to. 50% turface and 50% pumice.

Trim the roots, put it in the medium and wait for spring. But my A. asterias is inside. It doesn't know anything about spring vs. winter and it is shriveling even more now.

Seeing as how this cactus is inside where it is warm with a good source of moving air. Should I not perhaps moisten the growing medium in an effort to promote root growth?

Help quickly please!

Since light conditions may not be appropriate, here's what i would do.
1. Get one of those pot water trays. Fill it with stones and pour water in it.
2. Place the pot over the stones and keep the stones well wet with the water very slightly touching the bottom of the pot.
3. Compliment the natural light with a 6500K cfl bulb.

Make sure it is in a hot location and keep it that way for a month or 6 weeks. Then you can remove the tray and water the soil directly

[WayneByerly]

This is where I have my A. asterias ... you can see it in the center in the round unfired clay bowl. this window gets about 5 or 6 hours per day of direct sunlight (depending on which side of the window a plant sits in, and the CFL's are on 16 hours per day. Plants NEED 8 hours of darkness for proper photosynthesis.There are the two CFL's that you can see in this view, one just to the right outside of the picture boundaries and 2 more for the shelf underneath and another freestanding CFL for a total of 6 in that window area. they are 60W 6500K bulbs. I used info from the electric company to calculate what it cost me in electricity to run all of my "plant lights", and depending on what current rates and current fuel adjustments are, it costs me about $16 to $20 per month. but then we have some of the lowest electric rates in the country.

1.jpg (106.29 KiB) Viewed 1970 times

closeup of the A. asterias. as you can see from the photos, it's dark outside. and cold as a witches ... well, it's cold. so i'll wait until tomorrow to fetch stones for the round Drip/Humidity Tray underneath.

2.jpg (98.39 KiB) Viewed 1970 times

Thanks for responding. this cactus is 4 years old, and is really one of my favorites. I'm just heartbroke that I have treated it so poorly ... as in NOT the way it WANTS. They are fairly common, and easy enough to buy, but a replacement would NOT be the one i've taken care of for 4 years and probably not 50mm wide.

[WayneByerly]

content deleted by author as a duplicate.

[WayneByerly]

Hello Steve Johnson, hegar, keith, stefan, & Hanazono:

Sorry for being so long getting back here. My health is not good and the forum was down for a little while.




I no more than got my 15lb box of pumice than I started repotting some things ... at your suggestion. The first was my Astrophytum asterias which was 100% pumice/turface. The turface is a tad pricey, and considering my limited income i only bought a 2 gallon bag.

So there were only a couple that I made 100% mineral. I made a soil mixture that was 80% or 90% pumice and the remaining % a cactus potting soil mix for some of my other cacti that weren't QUITE so particular. I thought that for SOME cacti there NEEDED to be SOME organic material to the mix or they would starve unless frequently fertilized.

I repotted another one of my "inside" cacti. I immediately noticed, much to my chagrin, how damp the growing medium (soil) was in the bottom of that pot. I KNOW that cacti don't like to stay damp like that. HOW could I have created a soil that had SO much organic content to it. My own personal soil, based on what I had read, was somewhere in the vicinity of 50 to 60% mineral ... and maybe a little bit more mineral (and maybe sometimes a little less mineral) depending on how well it got stirred when I mixed it.

So after seeing how damp the bottom of that first pot was, I started repotting cacti with that 80/90 soil mixture. They were ALL damp in the bottom ... what I was doing, repotting with such a high percentage of mineral content, HAD to be having a beneficial effect, even if it weren't so immediately obvious.

and i've started a new-ish watering scheme ... i weigh the plant/pot/soil when it is completely wet, just after having watered it (using the gram scale on my $10 kitchen scale from amazon). and I write "Wet={that_weight}" on the back of the plant label. Then I weight the plant/pot/soil again several times over the next week and write the date and weight on the back, noting how much weight the plant/pot/soil has lost from the preceeding weight ... and I keep track of those weights. I've discovered that the rate-of-water-weight-loss starts out high and decreases gradually over time and then drops off considerably when the plant/pot/soil is DRY. I then write that on the back so that I know how many days it took for the plant/pot/soil to go completely dry. Now the back of my plant tag looks something like
1-Jan 303 Wet
2-Jan 293 10
4-Jan 273 10
5-Jan 265 8
7-Jan 255 5
8-Jan 250 5
9-Jan 248 2
Dry @ 248 over 8 days

Now I can get rid of all the writing prior to "Dry @ {weight} over {n} days", and I can write just the date that I water it and know that I need to check it again in a week to 9 days.

I know that this seems to be a fairly labor intensive process, but it IS a labor of love, and it DOES take a lot of the guesswork regarding WHEN to water out of the process.

Note: I have discovered that my deeper pots (and I have a number of them) have a tendency to stay wet (or damp) in the bottom, a LOT longer than the surface soil does. So if i were to depend on the condition of the surface soil to tell me when to water, then the bottom soil would STILL be damp or wet when I watered. And we are trying to DRY THINGS OUT BETWEEN WATERINGS HERE AREN'T WE? So the weighing process described above IS fairly effective in ensuring that the soil dries out between waterings.

Remember that cacti disallowed - see forum rules to do this. In xeric conditions, the hairfine roots that soak up water die. And then when water comes along again NEW hairfine roots grow to soak up the water on a fairly rapid basis. This is how NEW roots form. Cacti have disallowed - see forum rules to live like this. This is the way they WANT to live!

So OUR responsibility goes like this to ensure that they thrive and not just survive ... find that place ... that degree of dampness between wet and dry so that the cactus is ABLE to thrive without killing its roots with too much water. And REMEMBER that every cactus has it's own desire about when it should get water. That they are NOT all the same. That the general rules that we use to let cactus dry out between waterings is just that ... a general rule, and NOT one set in stone for EVERY cactus species.