Adding Perlite

[ricklynchcore]

Is it my understanding we have changed the recommended potting mix to now include perlite mixed in at every level?? I have used miracle grow potting mix with very good results here in Chicago. I used tomato tone, with dolomite lime. The perlite is a new recommendation correct? What does it achieve? Next season can I add it just to the additional mix or is it recommended to replace.

Thanks

[Zana]

I add it to potting soil mix, especially as I reuse from year to year (unless there were diseased plants in those containers. But each spring I add compost, some perlite, possibly some lime and sometimes some organic fertiliser or fish emulsion. I find the perlite helps with keeping the mix from becoming too compacted and with retaining moisture longer.

Up to you whether you use it or not. However I definitely find a great benefit in using it, since I don't have to water all the pots/containers as often. Although I have no real garden for veggies here at the house this year, the previous year I had somewhere between 120 and 150 pots/containers of varying sizes. Some as large as 90cm/3ft diametre and almost that deep. All of which sat on a concrete patio in a south facing backyard. The last year I had my "jungle" as my father calls it, I had to water at least twice a day when temps got up into the 30's Celcius (86 Fahrenheit and above) for the better part of 2 plus months....along with little or no rain. Quite the opposite of this year of cold and wet.

Whichever way you choose to go....its your choice.

[rnewste]

Rick,

I highly recommend adding to your Miracle-Gro Potting Mix, Perlite in a 4:1 ratio (20% Perlite). This will keep the MG from compacting too much, and will keep wicking consistent over several seasons of use. Home Depot as well as full service Nursery stores carry it.







Ray

[beeman]

Originally Posted by rnewste

Rick,I highly recommend adding to your Miracle-Gro Potting Mix, Perlite in a 4:1 ratio (20% Perlite). This will keep the MG from compacting too much, and will keep wicking consistent over several seasons of use. Home Depot as well as full service Nursery stores carry it.Ray

I was lead to believe that Perlite didn't hold water. It will keep the soil from compacting, but wouldn't vermiculite be a better choice for water retention?

[rnewste]

beeman,

The problem with most of these commercial potting mixes is that they retain TOO MUCH moisture in SWC applications. Perlite acts an an inhibitor, where Vermiculite would retain moisture, which is not a good thing in this specific application.

Ray

[Zana]

According to wikipedia, perlite does help to hold/retain moisture.

[rnewste]

Zana,

Perlite is a form of "exploded" natural glass. Is is less than 1% water soluble. Unlike Vermiculite, I don't think it "absorbs" moisture. I love its properties that make the 4:1 mix combo light and airy. Pro-Mix BX and HP versions contain generous amounts of Perlite.

Ray

[amideutch]

Perlite does hold moisture, but not as much as Vermiculite. For SWC's Perlite would be the better choice when trying to control water retention of the aggregate and aiding in the aeration of as well. Ami

[ricklynchcore]

Good answers, thanks all

Rick