What happens if the pellets dry out?

[Rothrock42]

I've read several different tutorials and blog posts on preparing the LECA for use and almost all of them have a very dire "Never let the pellets dry out." kind of warning.

But they never back that up with a why.

What happens if you do? Does the sun go dark? All the unicorns will die? What?

I'm wondering if you can do the initial rinsing and rounds of soaking, then let them dry. And then, when you need them, get away with a shorter, simple overnight soak? Or is there something "activated" that once it gets wet and then dries it can't go back?

[Salixx]

I have no idea, can't say I've heard that personally. I often am shifting plants around and disinfecting LECA in boiling water. I then set it out to dry so I can pack it away. I have also gotten super busy before and plants growing in S/H have dried out completely. While I don't like doing that often, nobody seems the worse for the wear.

As for faster soak times, I like straight up boiling it before even the first use. I boil for 10 minutes, let it sit for another 10 then dump the hot water out and fill the pot with cold water. I let that sit for a bit, dump and fill with cold water again and then it's usually luke or about room temp and read to go.

[Rothrock42]

Thanks Salixx. My guess is that they mean, don't let it dry out before you use them, because if you do you will need to soak them again. Good to know that it can be packed away.

[fishmom]

LECA is pretty absorbent when it is dry, so if you use it dry, it might tend to suck moisture out of the roots it is contacting, which is definitely not what you are looking for. As long as you soak it again before using, it should be fine.

[Ellen H]

I rinse and pre-treat my LECA as per Ray's instructions on his website, usually I have quite a bit left over (not potted) and it stays in a bucket and dries out. I just re-soak it overnight before potting up the plants. No worries.

[Rothrock42]

Ellen H -- Thank you good to hear from experience. It is just that the tutorials make it sound so dire.

[Ray]

If the LECA in a semi-hydro pot dries out regularly, then you're really not growing in semi-hydro culture, but in traditional culture using LECA as the medium.

One of the best reasons for not letting it dry out is that the rate of mineral and waste buildup in the medium will be drastically reduced.

[Rothrock42]

Thanks Ray. The instructions I was referring to talk about drying out between the initial rinse/soak and use.

I just wanted to be sure that they could go dry at that point, as long as they got a good soak before use.

[nogreenthumbs]

Originally Posted by Rothrock42

Thanks Ray. The instructions I was referring to talk about drying out between the initial rinse/soak and use.

I just wanted to be sure that they could go dry at that point, as long as they got a good soak before use.

I think this is sort of only for a special circumstance. Lets say you soak your media and get it ready to use, then you decide you won't need it for several days, so you lay it out and let it dry completely. Then when you're ready to use, just just throw it all together. The media being dry (if it has dried completely) is probably going to absorb a fair amount of moisture and may desiccate the roots of the plant since it could conceivably suck moisture out of the roots. In that situation, I believe, you would just need to give the media a soak in plain water (probably not needing to do epsom salt or multiple rinses or anything like that) just to hydrate the LECA before use.

If you want to do all of the presoaks and then you won't need the LECA for weeks or months, I assume there's absolutely no problem with drying the LECA and then using it later (but you'd probably want a soak (8-12 hours?) before you use it to hydrate it really well so it doesn't absorb all of the moisture in the reservoir or worse yet, the moisture in the roots.

[Ray]

Originally Posted by Rothrock42

Thanks Ray. The instructions I was referring to talk about drying out between the initial rinse/soak and use.

That's no problem whatsoever. The pellets go through a few wet/dry cycles before we even see them:

• Dry clay is mixed with water and binders at the factory.
• They are then pelletized and allowed to dry.
• Then they are fired, to bind them onto the permanent consistency we see.
• As the fired pellets exit the kiln, they are sprayed with water to cool them, and keep down dust.
• They are air dried, classified, and packaged.

The added binders, many of which are polymers based upon sodium salts, and (likely non-potable) water used will leave residues in the LECA, so that's why it's a good idea to soak it well before use, and extract them. I don't thinks it's that big of an issue,especially for less-sensitive foliage plants, but orchids can be a bit more sensitive. Adding Epsom salts and/or calcium nitrate (a tablespoon per gallon is adequate) to the soak water accelerates the extraction, and adds nutrients.