I’m testing my young orange tree with a ph tester, and noticed the soil is too far on the acidic side. I was wondering if the leaves fallen from my California pepper tree would help to balance the levels out?

 

 

Never dig anything into the soil under your citrus tree or all the fruit will fall off. You can use leaves of California pepper tree as mulch if you want but one could find better mulches. When any organic mulch rots, including leaves of California pepper, it will gradually add more acid. If your orange tree is doing fine I would not worry about what the soil test says. Most likely the deeper soil is alkaline. My experience is that if you simply follow all the rules of good gardening and give each plant what it needs, everything will be healthy and one never needs to use a soil test. For example, unless one is gardening in decomposed granite, our water and soil here in California is mostly alkaline, but let’s say you have camellias and azaleas, then you add all your coffee grounds and tea leaves and that fixes it. If you have decomposed granite soil, try to grow plants adapted to acid soil. I have gardened in this soil, however, and found everything thrived, so no problems!