Soil pH: The Simple Guide For Gardeners

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GIM ph Scale Simple 

Discussing soil pH can get technical rather quickly, which is why many gardeners – or anyone with a yard and landscaping, for that matter – often avoid the subject matter and hope it works out. You fertilize, water, weed, and the plants get plenty of sun… so that should be enough, right? Unfortunately, improper soil pH can ensure your yard or garden will be barren and stay that way. Along with horticultural fertility, the pH also affects your soil’s microbiology. Improper balance drives away beneficial organisms who live in a symbiotic relationship with the plant and soil; each benefiting the others’ health.

Don’t ignore your soil’s pH balance because it sounds complicated – in the details below we make understanding it simple. The following are the bare necessities that can help you:

Understand what pH is

Why pH balance is important

Checking and Changing the pH balance

Raised Garden Bed Advantages for pH Management

Popular vegetable pH preferences

Understanding What pH Is

When we discuss pH, we are measuring the alkalinity or acidity of a substance. It’s a scale that runs from 0 to 14, with 0 being the most acidic and 14 being the most alkaline. That means a pH of 7 is neutral (neither acidic or alkaline). You can do your own research into the terms acidity or alkaline, but you really just need to know how the scale works, paired with the needs of different vegetables.

The soil you’re using will most likely be between a pH of 3-10 depending on its composition and rainfall. Generally speaking, your garden’s plants will prefer soil with a pH of 6.5, making it slightly acidic. They usually can enjoy a range, so don’t worry about it being perfect. Plus, pH doesn’t change overnight, so you won’t wake up one morning and everything in your garden is dead.

Why pH Balance Is Important

Any extreme on the pH scale is going to have detrimental effects on your garden. The goal is to have soil erring near neutral with it being acceptable to lean slight acidic or alkaline. A soil’s nutrient availability is intrinsically related to the degree of pH. Keeping soil in a 6.5 to 7.5 pH range generally makes nutrients the most readily available for plants to absorb.

If the pH level becomes too low or too high, toxic levels of absorbent minerals are released and the plant poisons itself. Symptoms can be yellow, brown-spotted, and dead leaves. If these symptoms appear, don’t immediately jump to toxic soil. First check that your soil is moist an inch into the ground and reevaluate your garden’s sunbathing time. If those things aren’t the issue, then it’s time to check the pH balance of your soil.

Checking and Changing the pH Balance

PH meters can be purchased from your local gardening store, and that’s all there is to it. Prices range, but a decent meter can be purchased for around $14 which, considering the potential garden-saving information it reads, is worth it. Also, they usually include moisture measurement capabilities, saving you from sticking your fingers in the soil every morning to double check. If you’re concerned about your pH, buy a meter and use it to determine your soil’s acidity/alkalinity.

Now that you know a reading of 7 means neutral, any other number will fall on the side of alkaline or acidic.

What if it’s a Few Points Off in Either Direction? How do you Rebalance Your Soil’s pH?

Just remember: limestone raises and sulfur lowers. If your pH is too low, then add limestone. If your pH is too high, then add sulfur. It is simple, but there are some caveats. They are not water soluble, so don’t try to mix with water and spray over your garden. Limestone and sulfur also come in pellet form, which is easier to spread within your soil. Make sure you work it in the soil if you want it to be fast acting, or just throw it on top for a slower absorption.

Pro Tip: Use a raised garden bed if you want to have better control over your soil’s pH balance. Instead of planting in soil that might not be conducive to your garden’s health, a raised bed lets you plant in fresh soil meant for gardening. They drain well and the soil stays looser which is optimum for root growth. If you grow plants with differing tastes in pH, then you can garden with two raised beds – each with a different balance. Basically, raised beds offer more control over your garden AND soil vigor.

Lime – Image Source: Royal Horticulture Society

Elemental Sulfur Granules – Image Source: Planet Natural

Popular Vegetable pH Preferences

The final thing you need to know is what vegetables prefer what pH balance. The following are a few popular vegetables you’re bound to have in your garden. Now get out there and grow your best garden yet!

Vegetable

pH Balance

Asparagus

6-8

Beet

6-7.5

Broccoli

6-7

Celery

5.8-7

Cucumber

5.5-7

Lettuce

6-7

Sweet Pepper

5.5-7

Pumpkin

5.5-7.5

Spinach

6-7.5

Tomato

5.5-7.5

Authors: Wiley Geren III & Bryan Traficante


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