weird question. top dressing with old potting mix

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71GTO
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weird question. top dressing with old potting mix

Post by 71GTO » March 21st, 2021, 2:40 pm

So, aside from trying to get the lawn and landscape looking nice. I also grow fig trees in pots. Every few years I root prune them and replace as much of the potting mix as I can. So I have to do it again this year and I'm going to have a lot of this mix to dispose of. Its mostly peat moss, decomposed pine bark, perlite. I do add some lime and fertilizer during the growing season. Would that hurt the lawn? Even if its not a significant help at least I won't be throwing out like 20 garbage bags of mix.

71GTO
Posts: 178
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Re: weird question. top dressing with old potting mix

Post by 71GTO » March 21st, 2021, 3:38 pm

I just realized I posted this in the warm season section. I have a cool season lawn... I delete it and repost if I could.

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MorpheusPA
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Re: weird question. top dressing with old potting mix

Post by MorpheusPA » March 21st, 2021, 3:41 pm

It's not a significant help, no, as I assume you're using something like that decayed 5:1:1 mix that's been sitting around in the pot. If you're following that mix from that fellow over on the other place.

It's old OM, so there's nothing wrong with it. It won't feed the soil, it won't really add much except for some ancient OM, and it has few resources, being pretty tapped. It's OK, and 20 bags over 10,000 square feet doesn't amount to all that much.

The Perlite will hang around, but it's not going to cause any issues. You may notice white bits atop the soil, but that's just the volcanic glass bits, and completely harmless.

It's far better than dumping it into the trash, where it's a significant phosphorus pollutant and metal problem, so I'd definitely spread it on the lawn rather than do that, however.

(Don't worry about where you posted it, it doesn't really matter, or it can be moved).

71GTO
Posts: 178
Joined: July 10th, 2016, 3:42 pm
Location: Central NJ
Grass Type: Northern mix
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Re: weird question. top dressing with old potting mix

Post by 71GTO » March 21st, 2021, 4:02 pm

Thanks! I use pro mix HP from a nursery supply store. I think it similar to that mix, but I gave up mixing my own soil.

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MorpheusPA
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Re: weird question. top dressing with old potting mix

Post by MorpheusPA » March 21st, 2021, 4:10 pm

Yeah, it's annoying to make one's own, not really worth the time except for some specialty plants that really need it (like the Fiddle Leaf Fern), and doesn't help that much. I bother for my desert roses, which are extremely particular about a sandy soil. But I don't in all other cases.

A quick glance shows more bark fines instead of middling size bark, so same thing. It's no harm, some minor help (in terms of old OM). I'm calling it about the same as a real thin layer of peat moss, but far better than throwing it out and you might as well get some use out of it, one last time.


71GTO
Posts: 178
Joined: July 10th, 2016, 3:42 pm
Location: Central NJ
Grass Type: Northern mix
Lawn Size: 10000-20000
Level: Some Experience

Re: weird question. top dressing with old potting mix

Post by 71GTO » March 21st, 2021, 7:56 pm

It is annoying, I gave up after the place an hour away stopped carrying the pine bark mulch. Thank you again!

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