Monkey puzzle tree turning brown after moving
Thank you for your question about your monkey puzzle tree. Are you aware of (1) whether the root ball was thoroughly watered before being excavated; (2) the size of the root ball; (3) the size of the hole in which it was planted, (4) whether the hole was thoroughly watered before planting; and (5) what soil and planting techniques were used? I asked because all of these are important when moving a tree of this size, whose roots may extend 10 to 20 feet down, and 6 to 12 feet across.
A scientist from the University of British Columbia answered thus to a similar question:
"In my experience, monkey puzzles transplant welll, as long as the plant is healthy, the new soil profile is not too different from the original. and the vast majority of roots (along with attached soil) are undisturbed. The larger the tree, the more difficult this is. Feeder roots at the root ball margin are likely to have been lopped off. This may cause some corresponding dieback of actively growing parts of the tree. This is probably the reason for the tip dieback you are seeing. In this area, the entire branch usually dies back when this happens.
In horticulture, as in most other spheres, there are no absolutes. You can easily over-water a monkey puzzle tree, particularly one where the roots have been severed. Keep the soil moist, but not wet. Watch the leader and the branch tips, if you see the damage spreading, this probably represents dead roots -- either killed initially in the transplanting or rotted after drowning. On the other hand, if there were significant air pockets created beside intact roots when the tree was settled into its new home, those roots could have died due to drought (i.e., even despite religious irrigation).
To encourage new roots from old, you need both moisture and air (as well as adequate warmth and sunshine). Pay attention to the transition between your soil and the root ball. If there is a radical discontinuity (e.g., if your soil is clayey and the prepared hole has glazed sides), the roots may not penetrate into the new surroundings. Finally, if the soil textures are significantly different, water may accumulate (heavy soil = clay) or drain away (light soil = sand) on either side of the transition, and this will diminish the capacity of the roots to grow to the other side.
Because monkey puzzle is only moderately frost-hardy (USDA Zone 8), there may be a tendency to "protect" the plant by piling mulch over the roots, but doing could reduce oxygen diffusion below the surface, so moderation is probably the key."
I hope this is helpful to you. Good luck!