Before you start planting, it’s important to know the soil’s pH since not all plants require the same range of soil acidity.
Alkaline soil, or “sweet soil”, has a higher pH than acidic soil. The pH scale ranges from 0 to 14, with pH 7 being neutral . Soil with a pH of 7.0 or above is considered alkaline, while below 7 is acidic.
Read on for a list of plants that you can grow in alkaline soil. But, be sure to test the pH of your garden soil using a test kit before you start planting.
Vegetables That Thrive in Alkaline Soil
It’s time to start buying the vegetable seeds you wish to grow after you’ve determined whether your soil is alkaline, neutral, or acidic.
You may produce a wide range of vegetables in alkaline soil. However, many of the veggies on this list require frequent watering and at least 6 hours of sunlight per day.
Here are 23 alkaline-tolerant vegetables to grow:
- Broccoli Rabe
- Swiss Chard
- Bok Choy
- Brussel Sprouts
- Pole Beans
Most culinary herbs thrive in soil with a pH range of 6.0 to 7.5, which is slightly acidic to neutral. However, some herbs prefer alkaline soil while others are flexible.
Here are 7 best herbs for gardens with alkaline soil:
- Bay Laurel (bay leaf is used as an herb in cooking)
Best Fruit Trees for Alkaline Soil
Some fruit trees are alkaline tolerant plants while others thrive in different environmental conditions. Below are 10 fruit trees that like alkaline soil.
After testing your soil, go ahead and plant these alkaline-friendly plants if the pH is at an ideal range.
- Prickly-Pear Cactus
- Goji Berry Bush
- Passion fruit
- Mamey fruit
- Pistachio Tree
Houseplants That Like Alkaline Soil
Just like your favorite flowers and veggies, indoor house plants have a specific pH range in which they thrive best. Therefore, it’s important to check the soil in their pots and containers every so often, to make sure they’re growing in the best possible soil.
Some house plants love alkaline soil, but most prefer a neutral to mildly-alkaline potting mix. Below are 5 houseplants that you can grow in alkaline soil:
- Aloe Vera
- Asparagus Fern
Flowers for Alkaline Soil
There are a variety of flowering plants that thrive in alkaline soil. We’ve included 5 on this list. Choose your favorites and get planting!
- Lily of the Valley
- California Poppies
How to Make Soil More Alkaline
First, it’s important to know what type of soil you have. Is it chalky soil, peat soil, sandy soil, clay soil, or silty soil?
It could also be a mixture of more than one type. For example, loam combines sand, silt, and clay soil.
The next step is to test the pH of your garden soil. Below we’ll look at how to increase soil pH organically.
Step 1: Test Your Soil
To test the pH of your soil at home, get a soil test kit from a local garden center or online. Alternatively, get it tested at your local extension office.
Step 2: Raise the pH Naturally
To increase the pH of your soil naturally, there are a few things you can do.
Once you’ve figured out how much you need to increase the soil pH and what you need to use, it’s time to incorporate it into the soil.
Use a tiller, rake, shovel, or any other tool to do this, but make certain that the amendment of choice is well blended into the soil.
Below are some options to raise your soil pH organically.
1. Garden Lime
Using garden lime is a common way to raise soil pH levels for crops that grow best in alkaline soil. The quantity of limestone you use may vary based on the demands of your soil.
The average quantity is 1 cup per 50 square feet of garden. However, lime may burn plants if used in excess, so do not overdo it.
2. Wood Ashes
Using wood ashes is a cheap way to increase soil pH, although the results aren’t as long-lasting. Apply wood ash to the soil’s surface and water well. A basic guide is to apply 20 pounds for every 1000 square feet of garden.
But, be careful when applying as not all plants like wood ash. Ashes may harm certain plants such as blueberries and azaleas, which thrive best in acidic soil.
3. Baking Soda
Baking soda is another option that works well to make the soil more alkaline. It is also a fast and simple way to save money.
Even though it does not last as long as lime, baking soda is capable of producing benefits in less than two weeks. Moreover, used in the correct proportion, it is fairly mild on soil and plants.
For every gallon of water, add one tablespoon of baking soda. Use this ratio as a guide for larger or smaller applications.
However, as it can create an imbalance, don’t use too much baking soda in your garden. Repeat every few months or so to keep the soil pH at its ideal level.
Step 3: Water the Area Well
Ensure that the soil is well moistened, but not waterlogged. Overwatering may have negative effects, including leaching minerals and nutrients from the soil. So, be careful not to overdo it.
Step 4: Test the Soil pH Again After a Few Months
You’ll want to test the soil every few months to see whether the pH has changed. This will determine whether you utilized the right quantities and if the method is still effective.
Because limestone decomposes more slowly than wood ashes or baking soda, it will remain longer. But, the benefits of a high soil pH may take longer to appear.
See Also: 53 Plants That Thrive Well in Acidic Soil.
As your garden’s soil condition varies, so does the soil pH level. So, frequent testing will help you choose the right soil for plants that prefer alkaline soil.