Q.Remedy For Yellowing Needles On Japanese Umbrella Pines In Pots
Hello Gardening Know How: I have two Japanese Umbrella Pines that were transplanted from Portland, OR to Santa Barbara, CA (about 1 yr ago) and noticed the needles starting to yellow in late Oct. The trees are about 5ft tall (from soil top to tip) and the pots they’re in are 19″ in diameter with a soil height about 21″. I like to first know if the pot size is adequate for this size of tree? Second, since they are potted, do I need to be amending the soil more often, and if so, what type of product(s) would you recommend for this species, specifically? Any insights/advice appreciated as I really like these trees and would like to get them back to a healthier state. Happy Holidays!
Certified GKH Gardening Expert
You can add a layer of compost to the top each spring. (Remove some existing soil first.) To see if they are rootbound, pull them out of the pot a ways and check for circling roots. If they are, go up in pot size only one or two sizes. Add compost to the soil if you need to repot.
https://www.gardeningknowhow.com/ornamental/trees/umbrella-pine/umbrella-pine-planting.htm