Well, it sounds like that, in spite of your choice for a potting medium, you were very successful. If it works for you, keep it up. If you see a need to change, just read some of the many helpful threads in this forum. A search function can be found near the bottom of the main forum window, which will help you find info about specific topics.

Yes. I know that there is a lot of discussion about different potting medium, but my thoughts were;

Drainage is important and the sand and perlite give this.

Lightweight, perlite and potting medium do this

Moisture, the absorbent crystals in the potting soil provide this.

Time release fertilizer from the potting soil, compost and minerals from the soil are everything a plant needs.

I have to correct the post as the 4 unknown IDs were rhododendrons and not hydrangeas. I understand that these should have been done in the spring for best chance of success (or maybe only chance). So far 18 out of 18 with hydrangeas, arborvitaes and Chamaecypyris would indicate to me that the mix I used works well, as unconventional as it may seem.

correction "So far 14 out of 14.."

If you stay with plants fast and easy to root like hydrangea it does not matter what your starting medium is like. Other plants may take up to a year to root and will require a lot more selective rooting medium. Al

I'd skip the fertilizer until potted up or planted, and then go very light. Young roots are easily burned.

I usually root Rhododendrons in the Fall with hormones, bottom heat, and an automatic misting system. Same for most conifers that root too.

Hydrangeas are easy almost anytime.
My favorite is Weiderspink.
Mike
{{gwi:1081521}}

IMHO.. the problem with your media.. is that you put soil in it ... the two words are contradictory by definition ... and compost is just premature soil ...

also.. one of the beauties of media.. is the ability to sterilize it.. prior to use.. to remove bacteria, molds.. mildews.. and bugs ...

also.. a plant with no roots.. which you started with.. does not need fertilizer ... and excess of such [which since they need none.. all is excess] can cause rotting of cut green vegetation ...

congrats on your beginners luck ... if it works.. you win bragging rights ...

oh.. and in my z5.. terra cotta pots explode if they freeze ... they actually hold water within the cell walls.. and if that water freezes ... they crack ....pots that have been fired to a porcelain finish do not.. but neither are made for burying... now that you have a pot formed hole.. i would wiggle out the pot.. tip the plants out.. and nestle the wad of soil/media and plant.. right back into the form fitting hole... and a nice blanket of mulch over the edges will help temper temp fluctuations ....

experimenting is fun .. isnt it ... congrats again ...

ken

ps: also.. dont forget that a ROOTING MEDIA .. is not the same as a GROWING MEDIA .... so you wight want to start thinking about what media you what to pot them with next year ... if in fact you are leaving them potted ...

Here is a link that might be useful: sterilizing media

When you want a new generation of Hydrangea babies, you might like to try layering. You'll read all sorts of variations but for this easy-to-root plant, I just lay a brick or rock holding a stem to the ground. Have fun!