Soil Requirements for Plants-Part 1

Meeting the soil requirements for plants is a very important first step for the success of your garden. Have you ever wondered why your plants were looking less than spectacular? The leaves are yellowing or burning on the edges, or turning purple. Maybe new leaves are stunted or not the right shape. These are just some of the signs of mineral deficiencies in your plants. This may not mean the minerals your plants need aren’t in the soil, it could mean that your soil type is wrong for your plant. I’ll explain more in this article.Soil requirements for plants easy garden lifestyle

Soil requirements for plants.

I took a whole course at Agriculture College on soil management, so it’s VERY  important. And obviously, this is going to be a simplified explanation of soil types. They taught us everything we needed to know about soil requirements for plants.

One of the keys to success in gardening is knowing the soil requirements for plants. If your soil is the wrong type for your plant, nutrients can be bound up in the soil and unavailable to plants. But put the right plant in the right place and you have a happy plant. Alternatively, you can provide conditions suitable for the plants you want to grow. It’s like fighting with nature, but gardeners do it all the time.

If you don’t already know your soil type, then you should do a soil test. There are two things you need to know. Firstly, you need to know your soil pH, and secondly, you need to know your soil structure and there is a simple way to do this which I’ll cover in the next post.

For the first part, you need to invest in a soil pH kit. Take a sample from various corners of your lot because it can be vastly different from one corner to the next. The purpose of this test is to find out if your soil is alkaline, neutral, or acid. You may have heard the terms sweet or sour in terms of soil.  It just means that sweet soil is alkaline and sour soil is acid.

  • Very strong alkaline to slightly alkaline: 7.1-8.0
  • Neutral: 6.1-7.0
  • Moderate acid to extremely acid: 3.0-6.0

Even if you grow plants hydroponically, you must get the pH right for the plant.

Why is pH important for plants?

Soil pH is important for plants because it aids in nutrient uptake. That’s why, even though your soil has all the minerals your plant needs, your plant can’t do well because the nutrients are locked up in the soil and unavailable to your plants.

Luckily, most plants are happy in the slightly acidic, (5.1-6.0), to neutral range, but if you absolutely must have  blueberries and your soil is alkaline, guess what? Your blueberries are going to hate you. Why? Because they thrive in acidic soil.

Here’s a short list of plants that love slightly acid to acid soil:

  • Rhododendrons
  • Azaleas
  • Blueberries
  • Conifers
  • White potatoes
  • Moss
  • Gardenia
  • Mustards
  • Camellias
  • Cruciferous vegatables (Broccoli raab, turnip broccoli)
  • Soybeans
  • Sweet Osmanthus (Osmanthur fragrans)
soil requirements for plants


What if you are stuck with acidic soil and you desperately want to grow Hibiscus, which is in the pH range of 6.0-7.0? You can change your soil pH by adding soil amendments. The addition of lime will raise your soil pH to an acceptable level in which to grow Hibiscus or other neutral to alkaline loving plants.

If you have alkaline soil and you can’t live without growing your own blueberries, you can change the soil pH by adding Aluminum Sulfate to the soil.

You will have to keep adding lime or Aluminum Sulfate every yea,r or every other year, in order to maintain the state of your pH. The amount you add will depend on whether your soil structure is sandy, sandy-loam, loam, clay-loam or clay.

Unless otherwise stated, most non-soil based potting mixes will have a neutral pH, suitable for the vast majority of plants.  Some potting mixes are specifically made for acid loving plants. Peat based mixes lean toward acidic.  You could always make your own mix.

Soil requirements for plants

Worms are a good indicator of soil health.

So now you know why the soil requirements for plants are so important. If soil is too acidic it’s toxic to most plants and you won’t have any of those wonderful little micro-organisms and worms that are so good for the soil and the health of your plants. Equally, very few plants like to grow in chalk.

Here’s a tip.

You can tell a lot about your soil by the plants that grow there naturally… yes, the weeds! So find out what weeds in your area like acidic or alkaline soils and then examine your plot for an early indicator of your soil condition. You can also find out your soil structure using the very same method.

Did you know that you can change the flower color of your Hydrangea by adjusting the pH? If you know the answer about how to do this neat trick, leave it in the comments below!  


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