Which Plants Like Acidic Soil? (Plus 3 Ways To Acidify Soil)


The pH value of your soil has a significant effect on the nutrients that are available for your plants. If you recently discovered that your garden soil is on the acidic side, you might think your plant options are limited. 

On the contrary, there are a wide range of plants that thrive in acidic soil. Woody shrubs like roses, vegetables such as asparagus, and most fruit trees grow best in soil with pH levels below 7. 

While the above plants are known as acid-lovers, that doesn’t mean you need to rush to acidify your soil further. This article will discuss how to tell whether you should alter your garden’s pH level, how to do it, and give examples of plants that prefer acidic soil. 

Which Plants Like Acidic Soil?

Let’s start with a quick refresher on acidity levels, since if you’re anything like me, you may have assumed that you’d never have to worry about pH levels after grade school science. If you’re not, you already know that soil pH refers to the measure of acidity and alkalinity in a section of land. 

Acidity levels are measured using a scale of 0.0-14.0:

  • 0.0 is the most acidic on the scale,
  • 7.0 is considered neutral, and
  • 14.0 is the most alkaline.
soil
Soil with a pH of 7.0 is considered neutral. A pH below 7.0 is acidic, and a pH above 7.0 is basic or alkaline.

Anything that registers below a pH of 7.0 is considered acidic. Although this can be broken down further into degrees of acidity (such as slightly or moderately acidic), this article will use a broad overview. 

Here are some popular ornamentals and shrubs that grow well in acidic soil:

N
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m
e
Z
o
n
e
p
H
T
y
p
e
Bleeding
Heart
2-96.0-6.5Herbaceous plant with heart-shaped
flowers that bloom from spring until
summer.
Light shade to full sun.
Ostrich
Fern
3-75.5-6.5Deciduous plant with green fronds
that reach heights of up to 4 feet tall.
Part shade to full shade – keep out
of direct sunlight.
Bee
Balm
3-96.0-7.5Flowering plant with red, pink,
purple, or white blooms in
summer.
Full sun.
Creeping
Phlox
3-96.0-8.0Herbaceous flowering plant that
blooms in late spring to early
summer.
Full sun to partial shade.
Rhodo-
dendron
4-84.5-6.0Large genus of trees, shrubs, and
vines that bloom from spring – fall.
Full sun in zones 3-6.
Morning sun in tropical regions
(Zones 7-11).
Caladium/
Elephant
Ear
8-125.5-6.5Tropical plant with seasonal
dormancy in fall/winter.
Indirect light indoors.
Full to partial shade outdoors.
Daylily4-96.0-8.0Herbaceous plant which grows in
clumps that bloom from spring to
late summer.
Full sun to part shade.
Blueberry
Bush
3-64.0-6.0Upright bush with woody canes
that produce fruit in June.
Full sun to partial shade.
Pachy-
sandra
3-95.5-6.5Evergreen ground cover that
grows in partial to full shade.
Gladiolus8-105.0-7.0Flowering plant that grows from
bulbs and blooms from June
until frost.
Full sun.
This table gives an overview of some shrubs and ornamental plants that like acidic soil.
Bleeding Heart (shade garden plant pink flowers)
Bleeding Heart is an herbaceous plant with heart-shaped
flowers. It prefers a soil pH of 6.0 to 6.5, and is hardy in Zones 2 through 9. This plants prefers light shade to full sun.

Note: If you’re not sure what your growing zone is, check out the US Department of Agriculture’s Plant Hardiness Zone Map.

Please note that while we’ve provided a general range for each plant’s growing zone, always read the information tags on any plant you purchase to ensure the particular variety is suitable for your conditions. 

Vegetables That Like Acidic Soil

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T
y
p
e
Carrot3-105.5-7.06-10 hours of direct sun each day
Potato3-104.8-6.5At least 6 hours of direct sunlight per day
Garlic1-55.5-8.06-8 hours of direct sunlight per day
Asparagus3-86.0-8.0Minimum of 8 hours of sunlight each day
Cauliflower2-115.5-7.5At least 6 hours of full sun per day
Bell Pepper 9-115.5-7.0At least 6 hours of full sun per day
Broccoli2-116.0-7.0Minimum of 6 hours of full sun each day
Celery2-105.8-7.0At least 6 hours of full or partial sun every day
Cucumber4-105.5-7.06-8 hours of direct sunlight per day
Squash3-105.5-7.0Minimum of 6 hours of direct sun per day
This table gives an overview of some vegetables that like acidic soil.
potato flowers
Potato plants can grow in soil with a pH as low as 4.8, which is fairly acidic.

Trees That Like Acidic Soil

N
a
m
e
Z
o
n
e
p
H
T
y
p
e
Sugar Maple4-96.0-7.5Minimum of 4 hours of direct sun each day
Dogwood3-85.0-7.0Prefers partial shade but can tolerate full sun
White Pine3-74.5-6.0At least 4 hours of direct sun each day
Apple3-85.0-6.5At least 8 hours of full sun per day
Spruce3-85.0-6.0Minimum of 6 hours of unfiltered sunlight each day
Birch2-65.0-6.56 hours of full sun per day
Hemlock3-85.0-6.06-8 hours of direct sunlight each day
Chestnut4-95.0-6.5At least 8 hours of direct sunlight per day
Willow4-106.0-8.0Minimum of 4 hours of unfiltered sunlight per day
Juniper5-95.0 – 6.06-7 hours of direct sun each day
This table gives an overview of some trees that like acidic soil.
Apple trees can tolerate a soil pH down to 5.0 (fairly acidic). They are hardy in Zones 3 through 8 and need at least 8 hours of sunlight per day.

Do Hydrangeas Like Acidic Soil?

According to the Texas A&M Agrilife Extension, many hydrangeas cannot survive in soil that is not acidic. Generally, soil with a pH of less than 5.5 is ideal for most types of hydrangeas. 

hydrangea flower
Many hydrangeas cannot survive in soil that is not acidic. A pH of less than 5.5 is considered ideal for them. Hydrangea flowers change color depending on the pH of the soil they are grown in!

Depending on the variety you grow, you can even change the color of your hydrangea’s flowers by changing the acidity levels. However, this is easier to do when you grow them in containers since you can better control the pH levels.  

Do Roses Like Acidic Soil?

Roses generally receive optimal nutrition when the soil’s pH is around 6.0. This works out for much of the eastern United States, where the soil is commonly slightly acidic. 

Rose
Roses like slightly acidic soil (meaning a pH of around 6.0)

If your garden is more on the alkaline side and your roses are thriving, there is no need to change it. Most garden centers carry fertilizer specially formulated for roses and will provide the necessary amount of acidity.

Do Tomatoes Like Acidic Soil?

Tomatoes are well-known acid-loving plants that prefer to grow at pH levels between 5.5-7.0. Some research indicates that tomato plants grown in alkaline soil do not yield harvests as successful as those produced in higher acidity. 

ripe tomatoes on vine
Tomato plants like acidic soil, preferring to grow in soil at a pH between 5.5 and 7.0.

Fertilizers formulated for tomato plants can often provide the nutrients they might not receive from the soil otherwise, such as nitrogen, phosphorus, and potassium.   

How To Acidify Soil

Before you make your soil more acidic, you should figure out whether it’s necessary. If you are currently growing plants that technically need more acidic soil than you have, but your plants are performing well, there’s no need to change anything.

But if your acid-loving plants seem to be struggling, here’s what you can try:

Step 1: Assess The Symptoms

Your plants are the best indicator of whether something isn’t quite right in the garden. Small, pale green or yellow leaves with comparatively green veins are common signs that the soil pH is too high.

chlorosis
Yellow leaves on plants (also known as chlorosis) may indicate that the soil pH is off (which can cause nutrient deficiencies).

You may also notice brown edges on any new growth. If acidity levels are indeed the culprit, your plant could eventually die. 

Step 2: Test Your Soil

Since symptoms of nutrient deficiency can overlap with other plant problems, it’s a good idea to test your soil’s pH before altering it. The easiest way is to pick up a soil testing kit at your local garden center. These kits can determine how acidic your soil is with considerable accuracy. 

soil test kit
Use a soil test kit to figure out if you need to change the pH in your garden.

Follow the instructions on the test kit. If the pH level is below 7, your soil is acidic, and you should consider other diagnoses for your plant’s health issues. If your soil registers above 7, then it’s considered alkaline. 

(You can learn more about what a soil test tells you here).

Step 3: Amend The Soil

There are several ways to decrease your garden’s pH levels and make it more acidic. According to Oregon State’s Extension Service, an easy way to alter acidity is to amend it with elemental sulfur or nitrogen fertilizer.

(You can learn more about which fertilizers are acidic here).

sulfur powder
You can use elemental sulfur (powder works faster than pellets) to acidify soil. However, there are other ways to do it too.

Working elemental sulfur into your garden is the quickest way to make it more acidic. When you mix sulfur with soil, thiobacillius (naturally occurring bacteria) oxidates it and creates sulfuric acid. 

Many experts recommend a more gradual approach compared to adding sulfur. Working fertilizer such as ammonium nitrate, urea, ammonium phosphate, or ammonium sulfate into the soil will slowly acidify it over several years. The type you choose will depend on how much of a decrease in pH you need. 

It’s important to note that using aluminum sulfate, while effective, carries the risk of side effects that can harm your plants and inhibit growth. 

Step 4: Be Patient

Patience is arguably the most difficult gardening-related skill to learn. Any change you make to your soil’s acidity levels could take years to notice an improvement.

zucchini squash
Keep an eye on your plants (here is some zucchini!) to assess how they are doing.

In the meantime, continue caring for your garden as you normally would, and observe your plants for any changes. 

Conclusion

No matter where you’re located, you shouldn’t have trouble finding an array of plant choices for acidic soil. In many cases, you can even stretch the boundaries of the recommended pH levels as long as you’re providing excellent care otherwise. 

You can learn more about good plants to grow in poor soil conditions (including dry, wet, sandy, clay, or acidic) here.

About the author:
Kathryn is a plant enthusiast and freelance content writer who specializes in home and garden topics. Based in New York, you can get in touch with Kathryn at https://kathrynflegal.journoportfolio.com/.

Kathryn F.

jonathon.david.madore

Hi, I'm Jon. Let's solve your gardening problems, spend more time growing, and get the best harvest every year!

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