Did I buy the wrong perlite?

[flowerpower]

Hi all

I have a mini Phal and a Nobile Dendrobium that require repotting. I use medium grade fir bark for my other Phals, but I thought these two plants might benefit from the added air and moisture that perlite could provide

However, I have come home with "horticultural grade perlite". It consists of small white granules.

Is this the wrong type of perlite - too small for orchids? I thought this is what everybody else was using

[Brooke]

Yes the hort grade is the type you would add to a peat or coir mix for house plants. They make bigger perlite for orchid mixes.

Brooke

[flowerpower]

So, no use for orchids in a bark mix then? Never mind I still have the receipt. Saying that, I have some other houseplants that might benefit from it.

Suppose it was silly of me to buy it but I thought it might expand when wet or do something miraculous. Wonder if my mini Phal and Dendrobium would be OK in straight medium bark as I did not see any other types of perlite in the shop

[berniep]

G'Day Brooke

The perlite I use in my mix is small about 3mm and the plants seem to like it, I use it coco husk and charcoal. about a handful of it and charcoal. Be careful not to breathe the dust of the perlite in.

Cheers
Bernie

[davetheorchidaddict]

All the perlite I have used was small but was a filler in the medium. I also use it in my mix for terrestials.

[kmarch]

There's nothing wrong with horticultural grade. You could use it. Personally the bigger size bark I use the bigger size perlite I use.

Be sure to take Bernie's advice about not inhaling the dust. You could use a mask or wet the perlite down before using it.

[LouisW]

I use the smaller grade in my Choir mix but if you are using bark I think its more likely to wash out through the drainage holes.

[berkeleysgr8]

I think the size you got is probably fine. I have a HUGE bag (it's even bigger than my 55 liter bag of Hydroton) of perlite from a hydroponics shop... I wish I had spent the extra money to get the chunkier perlite.

As a funny side note, a neighbor stopped by to chat me up last year. We were standing in front of my open garage. He eyed the Hydroton, perlite, coco husks and potting soil... he assumed I was growing marijuana. He didn't seem to believe me when I said I had about 100 orchids.

[Phoenix7801]

You shoulda shown him the orchids Berkeley. Seriously this one guy's neighbors called the cops because they said he was growing marijuana. Turns out it was just Texas Star Hibiscus (google that plant...seriously its funny)

[Brooke]

Horticultural grade perlite is too small to use with a bark mix. It will either wash out with watering or even worse, get lodged between bark pieces and reduce air space.

I use the hort grade with coir in a 50/50 ratio for terrestrials. If you follow Mayres recommendations for the phal mix, this grade is what you use.

Flowerpower you can use chunky bark only - like you, I have to purchase larger perlite from an orchid vendor.

I grow the Texas Star hibiscus - it is gorgeous when it blooms in late fall. I used to grow them from seed before all available space became occupied by orchids.

Brooke

[flowerpower]

Thanks all, I returned it earlier. It was only £1.49, but I think there is a chance it would move to the bottom and ultimately wash out through the drainage holes. I think I will stick to what I know for now and that's medium fir bark. Seems to suit my conditions well, I just wanted to experiment.

[Stitz]

Fir bark finest available (2 cu/ft bags) fine (1/8-¼) med

I purchased perlite (sponge roc) #3 and #4 from this vendor, to be found near the end of the link provided. I think that this might be what you are seeking.

[11Orchid126]

FirstRay's site has an article about using small perlite. He says it fills the air pockets that the roots need for survival.

[kid a]

they also sell the large kind at repotme Large Sponge Rock

[Stitz]

kid a,

Roberts Flower Supply sells a 4 cubic foot box for $25.95
repotme.com sells a 1 cubic foot box for $61.00

that's a no-brainer

[Brooke]

I bet the freight to London would make it really expensive

I use Roberts but I usually pick it up at a show from them.

Brooke