Vegetables for Alkaline Soils
Not all soil is created equal and not all plants will do well in all soils. Most vegetables thrive in soils with a pH between 6.5 and 7.0. Most of the soil tested in Hamilton County is considered alkaline, pH of 7.0 or higher. What can you grow in alkaline soils? Almost anything depending on HOW alkaline. There are only a few types of vegetables that will do well in with high soil pH - asparagus and garlic. The rest can generally be grown up in soil with a pH of up to 7.5 without a lot of issues.
Vegetables for Alkaline Soils
What is pH?
"Soil pH is the measure of the acidity (sourness) or alkalinity (sweetness) of a soil." (University of Vermont Extension) Soil pH measures on a numerical scale that goes from 0.0 to 14.0. A soil pH of 0.0 is the most acidic while 14.0 being most alkaline. A soil pH of 7.0 is neutral.
How pH Works and What it Tells You
Soil pH influences the availability of nutrients. Some nutrients are more available in acidic soil, whereas some nutrients are more available in alkaline soil. Go to far in either direction and nutrients can get "locked up" making them inaccessible to plants.
Soil pH influences plant growth through several factors. Those factors include soil bacteria, nutrient leaching, nutrient availability, toxic elements, and soil structure. These factors have equal importance. Yet, many gardeners tend to focus on nutrient availability. A soil pH in the right zone for a plant will make nutrients available to that plant. If there are nutrients, but the pH is too high or low, the plant will not be able to absorb the nutrients.
Testing Your Soil pH
Due to the factors that influence pH and the needs of your plants, it is best to have a lab quality soil test. A lab quality soil test will tell you what nutrients you have in your soil including the pH. You can use at home pH meters, but a lab analysis is our preference!
Click here to learn more about how to do a soil test.
Changing the pH of Your Soil
Soil chemistry and biology is both simple and complex. Thus, changing the pH can be simple or complex. If your soil is too acidic, a common way to raise the pH is by adding lime. Lime is short for limestone. There are multiple type of lime available to home gardeners. You can learn more about the different types by clicking here. If soil is too alkaline, one common method to lower the pH is by applying sulfur. There are also different kinds of sulfur. To know how much to add, and of what kinds of lime or sulfur, you need to test the pH of your soil. Adding too much can cause imbalances. A basic rule to follow is to start by adding a little and retesting year to year. Be aware it takes the work of the microbes and time to break down the lime and sulfur in order to alter the pH of the soil. You may have to do this annually until you reach the desired level of pH!
A soil test, which measures more than pH, is the best way to determine what your soil needs. Click here to learn more about how to do a soil test.
Sources:
The Old Farmers Almanac
Vegetables for Alkaline Soils
- Asparagus (6.0-8.0)
- Beans, pole (6.0-7.5)
- Beet (6.0-7.5)
- Brussels Sprouts (6.0-7.5)
- Cauliflower (5.5-7.5)
- Garlic (5.5-8.0)
- Kale (6.0-7.5)
- Pea, sweet (6.0-7.5)
- Pumpkin (5.5-7.5)
- Spinach (6.0-7.5)
- Crookneck Squash (6.0-7.5)
- Tomato (5.5-7.5)
What is pH?
"Soil pH is the measure of the acidity (sourness) or alkalinity (sweetness) of a soil." (University of Vermont Extension) Soil pH measures on a numerical scale that goes from 0.0 to 14.0. A soil pH of 0.0 is the most acidic while 14.0 being most alkaline. A soil pH of 7.0 is neutral.
How pH Works and What it Tells You
Soil pH influences the availability of nutrients. Some nutrients are more available in acidic soil, whereas some nutrients are more available in alkaline soil. Go to far in either direction and nutrients can get "locked up" making them inaccessible to plants.
Soil pH influences plant growth through several factors. Those factors include soil bacteria, nutrient leaching, nutrient availability, toxic elements, and soil structure. These factors have equal importance. Yet, many gardeners tend to focus on nutrient availability. A soil pH in the right zone for a plant will make nutrients available to that plant. If there are nutrients, but the pH is too high or low, the plant will not be able to absorb the nutrients.
Testing Your Soil pH
Due to the factors that influence pH and the needs of your plants, it is best to have a lab quality soil test. A lab quality soil test will tell you what nutrients you have in your soil including the pH. You can use at home pH meters, but a lab analysis is our preference!
Click here to learn more about how to do a soil test.
Changing the pH of Your Soil
Soil chemistry and biology is both simple and complex. Thus, changing the pH can be simple or complex. If your soil is too acidic, a common way to raise the pH is by adding lime. Lime is short for limestone. There are multiple type of lime available to home gardeners. You can learn more about the different types by clicking here. If soil is too alkaline, one common method to lower the pH is by applying sulfur. There are also different kinds of sulfur. To know how much to add, and of what kinds of lime or sulfur, you need to test the pH of your soil. Adding too much can cause imbalances. A basic rule to follow is to start by adding a little and retesting year to year. Be aware it takes the work of the microbes and time to break down the lime and sulfur in order to alter the pH of the soil. You may have to do this annually until you reach the desired level of pH!
A soil test, which measures more than pH, is the best way to determine what your soil needs. Click here to learn more about how to do a soil test.
Sources:
The Old Farmers Almanac