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Poor drainage, numerous pots


Question
QUESTION: Upon re-potting a number of plants, I am finding they have very poor drainage, where water drained right through before potting. Water just pools on top then meanders through and out the bottom over the course of literally ten to fifteen minutes. It has happened with two different concoctions and a total of 9 plants: peat/perlite and peat/perlite/vermiculite, both lightly tamped, not packed. The peat, perlite, and vermiculite are all espoma brand. I am carefully using equal parts of each and the bottom holes are of decent size.  Could it be the peat is the culprit, and if so can you recommend a brand to look for on Amazon.com? Others with poor experience ratings? I'm thinking this can't be good for the plants!

ANSWER: Hi Steve,

This isn't unusual.  It often takes peat moss awhile to fully hydrate and settle.  During this time it doesn't always drain well.  Try a 3 parts perlite to 1 part peat moss mix.  This will give you a much more rapid draining mix.  Avoid vermiculite altogether.  Vermiculite can be alkaline which carnivorous plants don't like.  Also, using equal parts peat, perlite, and silica sand can give you a very good fast draining mix.  We use that mix for our Drosophyllum.

We've used similar mixes for years with no problems.  This isn't something to worry too much about.

Good quality peat moss is getting to be a more serious issue with time just because the retail grades often have high mineral salt contents.  They require heavy rinsing, or rain exposure to leach it out.  Course growers grades are the best, but you have to get them from nursery supply companies.  This is where ours comes from, and it's excellent:  http://obcnw.com/theriaultandhacheypeatmoss.aspx  This is what all our mixes have in them except the tropical mix.

Good Growing!

Jeff Dallas
Sarracenia Northwest
http://www.growcarnivorousplants.com

---------- FOLLOW-UP ----------

QUESTION: Thank you, Jeff, for your answer and tips.  I'm sure I heard of vermiculite on your DVD's talking about potting the tropical Butterworts as well as the Nepenthes.  Can I set aside the opened bag for non-CP houseplants? Outdoor bed amendments? Literally only used enough to mix for a 6" pot, seems like a bit of a waste.

On a lighter note, I'm excited to see my upcoming 6th GPOM shipment!  Thanks again for sharing your gifts.  SNW has turned me from a proven plant killer into someone who doesn't HAVE all the answers but now knows WHAT, WHEN, and WHO to ask.

Best Regards,
Steve Milone

Answer
Hi Steve,

We have used vermiculite in the past, but have since discontinued.  We've just found over time it has disadvantages.  There's also some evidence that vermiculite can contain traces of abestos.  Adding it to regular plant potting mixes is a great use for it.

Glad you've enjoyed the plant, and that our information has been helpful.  What, When and Who is sort the motto for master gardeners too!

Good Growing!

Jeff Dallas
Sarracenia Northwest
http://www.growcarnivorousplants.com  

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