I have some small cuttings of Monterey cypress that I rooted in November and I would now like to replant them. What type of soil and pot should I use to get maximum growth?
Thanks in advance.
Hi @Forestcat
For maximum growth, put them in the ground or take a tip from the nursery industry, their business is all about getting plants to grow fast.
On the USA West Coast most nursery stock in pots is grown in mix that is based upon composted bark since it holds moisture and has a very high CEC (cation exchange coefficient) which makes applied fertilizer available to the tree. It produces lots of growth, but I don’t like the root system that is produced for bonsai. It seems to me that most of the roots end up on the outside and bottom of the pot vs. the interior. To me that seems like it would be the warmer, slightly drier parts of the pot with more air exchange since the composted bark tends to hold lots of moisture. The balance of water and oxygen seems to be off in my mind.
I believe that both Telperion Farms and Driftwood Bonsai in Oregon both use a mixture of composted bark, grit of some form, and composted manure in their grow bags to develop bonsai. The composited bark holds moisture and has a high CEC, the grit helps maintain the soil structure, and the manure is a solid organic fertilizer.
I am planning to use a mixture of about 40% composted bark, 40% pumice, and 20% composted steer manure in a bunch of pots for seedlings that I am developing for bonsai. I could also use lava, but the proper size became less readily available just when bulk pumice became available in my area. I plan to sieve all three to remove the big particles (either 9 or 12 mm sieve depending upon the pot size) and the smaller ones (3 mm). The larger ones are apt to end up in the bottom of the pot. In the UK, compost (coarse peat) is used instead of composted bark based upon some off forum discussion.
To get back to ForestCat’s original question, I would put his cutttings in pots the size they will colonize with roots in a year or two using a growing media like I described above. You can then decide if you want to grow them in the ground or continue in pots - I suggest shallower pots for most bonsai development if you take that route. This would be similar to the approach described in the Asymmetry podcast with Telperion Farms where they said they grow small stuff for a year or two in gallon pots to get the start of a nebari before they put it in grow bags in the field.
Thanks, Andy and Marty. I will post a progress repot at the end of summer.