Vance Wood

Here is what you can do now and into the fall. Snip out the unwanted growth, assuming you know what style or form you can make of this tree. You can also cut out this years new growth all the way back to where it started this last spring. It will start to form new buds in a couple of weeks that will shoot more compact growth and shorter needles in the spring.

I always repot my Mugos in the late spring, around Father's Day, through mid summer, into August, once the new needles have opened and extended, remember this is not a JBP. As to the soil mix I use equal parts A,B and C, by measure not weight, break down follows.

PART A: #2 or #3 swimming pool filter sand or sand blasting sand (same stuff).

PART B: Composted Pine Bark,

PART C: Truface or Red Volcanic gravel, or both together as one measure.

Mugos like more water than JBP but they don't like being wet, they must have drainage. The soil mix you propose is too austere, you need the organics in it.

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The only finished bonsai is a dead one; me 1992 MABA Des Moines Iowa