When we measure pH, we are measuring the concentration of hydrogen (H+) ions in the irrigation water or soil (nutrient) solution. As a guideline, water for irrigation purposes is usually best if its pH lies between 5.0 - 7.0. The measure of alkalinity gives us the water's ability to neutralize acidity. The level of bicarbonates, carbonates, and hydroxides in water determine its alkalinity. The desirable alkalinity range for irrigation water is 0 to 100 ppm carbonates, with 30 - 60 ppm optimum for most plants. Whenever you test the water you'll be using for irrigation, you should always include the measure of both pH and alkalinity. A pH test on its own, does not give any indication of alkalinity. Water with high levels of bicarbonates or carbonates (high alkalinity) always has a pH value >7, but water with a high pH doesn't necessarily have high alkalinity. This is a very important concept because high alkalinity exerts more significant effect on plant nutrition and the fertility of growing media than pH. High pH irrigation water generally causes no problems as long as the alkalinity is low. Since high pH water with low alkalinity has little ability to neutralize acidity, it's effect on media pH will be minimal. Cause for more concern are situations where you must utilize water having both high pH and high alkalinity for irrigation, which will cause the pH of the growing medium to increase substantially as media ages. If your water analysis is known to be alkaline, you may need to significantly reduce the addition of compounds containing Ca or Mg because of the dilute solution of limestone in the water. The smaller the container - the more serious the issue because small volumes of soil offer less buffering to pH change. In high alkaline situations, you can often expect/experience Ca and Mg deficiencies along with micronutrient deficiencies (both real and antagonistic). Acid forming fertilizer will not actually lower media pH as long as there is limestone in the soil - unless the soil is acidic already, but vinegar (and other acid) applications will help to neutralize alkalinity in the irrigation water, which will be helpful. Al

These are interesting further comments! Thanks! They have made me think & now have more questions (sorry!). I'm still siting the bb before double potting in 1/2 wine barrels in next week. Since they don't look rootbound, will hold off actual repotting until dormancy as long as they look healthy. I haven't decided on a soil mix yet. I know Username's works & it looks like bb really like a lot of organic matter. My intuitive response would be to use this kind of soil mix (I get all excited abt. compost, earthworms, etc. although I haven't yet learned how to make compost in our vy. hot dry climate). My other choice would be a (very)simplified version of the fast-draining soil mixes discussed on the Container forum. Since I haven't been able to find the aggregate that forms an important part of those mixes, I experimented by just cutting either potting soil or amendment 50/50 with fine bark mulch. I then potted up my bareroots in it. It seemed so counterintuitive, but everything (so far) has thrived. It seems (for this hot, dry climate) to avoid having the outer soil area overheat & dry out while inner area remains damp to wet. Yes, it sure does need a lot of watering! It seems, however, to be much less tricky to water, i.e., you can water a bit early without danger of overwatering. I had lost a couple of rosebushes from overwatering here in the desert. Lest anyone reading this thinks abt. using same type of mix, let me point out that I still need to study the possible components of soil mixes & that problems w. the mix I have used may develop! Best to study to mixes others have used successfully over longer period of time. Username, do you think it would be necessary to repot bb using mix you described in year--couple years, i.e., would soil start to compact? If anyone would like to suggest alternatives to peat moss which they have used, I'd love to consider them. Kimmsr, would you mean leaves which are then composted? I ought to have quite a few of them when my espaliered pear and apple trees have grown a bit. Nandina, thanks!! Sunshine Blue sounds like a dandy--it's on my list for next year. You are right, the name of the game with the climate here is experiment! Squarefooterg, That's interesting! How are the ground citrus peels used? Thank you all!

I learned this tip in an organic gardening class.... They also suggested using the citrus peel or citrus that had gone bad.... They said to cut in half, place face down and mulch in.... I haven't tried it yet..... He said acid loving plants you could apply every time you water and others you should do once a month or so.....

HI, If I were you I would not use the acid plant food it's probally to high in nitrogen. Instead I would apply sulfur in early spring and add lots of acid soil amendments like peat. The peat will take a while to break down but it should bring the soil Ph down eventually. The sulfur is more fast acting as would be the acidic plant food however it does not keep the ph down for very long. If all else fails raised beds work really well for tomato's.