Procumbens Nana Color is Changing Yellow

I have had this small piece of nursery stock for about 1 1/2 years. Last October it started turning bright yellow (partially). I stopped watering and left it alone throughout the winter. Last March I repotted it into a training pot and put it into equal parts pumice, lava, and acadama to ensure good drainage. The month of March in Southern California was unseasonably cool. Average temps in the high 60’s low 70’s. The plant was doing fine.

This week we had a temperature spike of mid 90’s and I have increased the watering for most all the plants including this procumbens. Again, it is moving to yellow see the pics below. I don’t believe it has aphids or other pests. If I stop watering I fear it may just croak but if I do water it much (two a day for the past two days of 95, 98 degrees) it is going back to its yellowing ways. Could it be water quality? Any advice would be helpful. I am new to Bonsai Mirai, and bonsai as well. I love everything about it… except this plant right now. (LOL)

What’s your water source? What’s its pH? Have you fertilized the tree at at? Have you given thought to nutrient deficiencies and checked the soil pH? Hard to see from the photos but it appears it the new growth and it may be nothing to worry about? If its the older foliage it may indeed be nutrient deficiency. Could be calcium, magnesium, iron or even potassium. One if my procumbens is lime-green right now but its just the new growth. If it begins to actually yellow I’ll add cal-mag liquid fertilizer to watering twice a week and adjust pH of my water to about 6.5. Good luck with your Procumebns.

Quick search and I found these to help you


These are very helpful. I just got my kit for testing Ph levels. The plant it self has robust growth but still the odd discoloring in various regions of the tree.