Yes. And soil pH micronutrient availability is the big one here, by far. Your soil pH is the master dial for it. The same nutrient can sit right there in the soil and stay locked up where roots cannot reach it. The amount in the dirt never changes. But the pH decides whether your plant gets to use it.
This catches a lot of gardeners off guard. You add the right feed. The leaves still go yellow. The test says the nutrient is present. So the block is chemistry, not supply. As the soil moves toward the alkaline end of the scale, several key metals turn into forms that roots cannot absorb at all.
Think of pH as the number that sets how soil chemistry behaves. It runs from acid at the low end to alkaline at the high end, with neutral sitting at 7.0. Most garden soil falls somewhere between 5.5 and 7.5. That small spread looks minor. But it is the difference between a nutrient that flows into roots and one that sits there like a locked box. It is also why two beds with the same fertilizer can look so different.
Here is the plain version of what happens. As pH rises toward alkaline, iron, manganese, and zinc bond into compounds that will not dissolve in soil water. Roots drink from that water, so if the nutrient is not dissolved, it might as well not be there. Molybdenum runs the other way and gets easier to absorb as pH climbs. That is why alkaline soil iron problems show up first and worst on high pH ground.
Iron is the one most people meet. Iron deficiency is common on alkaline, high pH soils, and it shows as yellow leaves with green veins on the newest growth. The plant has plenty of iron around its roots. It just cannot pull any of it in. Spread lime on that same bed and you make the problem worse, since lime pushes pH up even further.
Some plants feel this far more than others. Acid-loving plants are the prime example, and you may grow a few. The big three are the azalea, the blueberry, and the rhododendron. They grew up on sour ground. They are built to grab iron and manganese only when the soil sits low on the scale. Drop them into neutral or alkaline dirt and they lock out fast. This happens even when a soil test says every nutrient is present. The yellowing you see is a pH problem in disguise.
So test before you feed anything. A cheap pH meter or a mail-in lab kit tells you the one number that explains most mystery deficiencies. Match that reading against what your plant wants. Blueberries like 4.5 to 5.5, while most vegetables sit happy near 6.5. Once you know the gap, you know the fix.
If the reading is too high, work in elemental sulfur over time to bring the soil down toward the range your plant prefers. This takes patience, not a weekend. When lowering pH is not practical, such as in a lawn or a large bed near a concrete path, reach for chelated iron instead. The chelate wraps the iron and keeps it absorbable even on alkaline ground, so your plant greens up while you sort out the deeper pH issue.
One last habit will save you money. Retest the soil a few months after you add sulfur, then again the next season. Sulfur works slow, and the soil can drift back up over time near old concrete or hard water. A quick check stops you from chasing yellow leaves with feed you do not need. Fix the pH first, and the micronutrients tend to sort themselves out.
Read the full article: Micronutrients Plants Need: A Complete Guide
