Tomato: That’s blossom-end rot; a hard, brown, hollow spot at the end where the blossom was. It looks like a disease; it isn’t. The trouble begins underground, specifically in the soil, which has locked up some needed calcium that the plant counts on for making its cell walls.
The source doesn’t mention onions, peppers, eggplants, or beans being affected by blossom-end rot. The chart above illustrates how certain kinds of failure modes (iron starvation, calcium stalls) is created when the soil chemistry goes out of whack and the plant dies a slow death. Not only does it die; it suffer silently first.
How to Fix Your Soil for Healthy Plants
Soil pH is something most gardeners think of as the overall number for their backyards; they purchase lime, toss it onto the lawn, and call it balanced. Things go wrong because most don’t realize its a different story in every area of garden. How? The infographic explains that you should of split your areas into zones based off chemistry.
This tactic will keep acid-loving plants like sweet potatoes and other tubers happy by maintaining a lower pH so iron remains available. At the same time, it keeps brassicas, like broccoli and cabbage, more happier with a higher pH to help them get molybdenum and avoid clubroot. Feed only one side of your garden if you try to maintain an overall average, and starve the rest. It is a simple zoning issue that cause huge headaches later.
Another silent killer are timing. The chemistry doesn’t flip overnight when you adjust pH. How long it will take depend on the type of amendment used. This is outlined in visual guide, which shows lag times for each.
Elemental sulfur takes longest, being the slowest as it depends on microbes to acidify the soil (almost five months). Calcitic limestone provides a gradual seasonal lift so give it nearly three months until it settles. Hydrated lime is faster than rock but more caustic. Wood ash give an alkaline pulse in around two weeks; quick and fast.
Know your lag period. It’s important to manage expectations. Chasing readings weekly means you’re wasting money and time. Add more material? To a chemical reaction that hasn’t finished yet? No thanks. Wait it out.
And then there’s the story of phosphorus availability. That sweet spot is right around neutral up through slightly acidic conditions. Too much or too little on either end is like throwing dollar bills down the drain, they go into the soil where the roots can’t reach them. What you see out here… Your plants looking like they lack some element (isn’t a deficiency); it’s an availability issue, according to the numbers.
Target that top range, unless you’re growing a crop such as acid-loving potatoes, which ranks tops in the preference list and require a low end of the scale. Don’t plant and hope for the best; test first. Sample deeply into the root area of your major crops. How deep? Carrots and onions need deeper sampling different than lettuce because of their root zones.
After you take a core sample, add to only what’s needed. Over-liming is no good. You shouldn’t under-sulfur either just because you’re afraid.
Know your soil type, read up on which crops are happy at the extremes of low or high pH where you live, and make your beds accordingly. Group crops with similar chemistry together. No cabbages next to the potatoes.
Give the plants the nutrients they want, let the soil do its thing, then stand back and watch it go. Do less forcing of nature and allow more nature to go through the door to get what it wants.