Now, let’s be honest about the title of this post: it does sound a little silly, but talking about “bad soil” is very important. In reality, there’s no inherently bad soil; it’s more about finding the right match for your plants. Fortunately, most soil types can be enhanced with a few simple steps.
Originating from the Mediterranean, lavender flourishes in soils mirroring its native environment—poor or moderately fertile and, notably, free-draining. Lavender grows best in sandy, chalky, or alkaline soils. But what if you want to grow lavender in clayey, acidic, or clay loam soil?
Lavender is one of the most popular and recognizable herb plants, with its fragrant foliage and vivid purple flowers. However, getting it to thrive can be tricky if your soil conditions aren’t quite right. Lavender prefers neutral to alkaline soils with a pH between 6.5-7.5. So what happens if you try to grow lavender in acidic soil?
While lavender can tolerate mildly acidic soils down to pH 6.5, anything more acidic than that will cause the plant stress. Growth will be stunted, flowering reduced, and the plant likely won’t survive for long.
The reason lavender dislikes acidic soil is that it naturally grows in the alkaline, calcareous soils of the Mediterranean region. Therefore, to replicate its preferred native conditions, lavender does best in light, well-draining, slightly sandy soil with a neutral to mildly alkaline pH.
Fortunately, there are several solutions for successfully growing lavender in acidic soil:
Test Soil pH
First, test your soil’s pH to determine exactly how acidic it is. Home soil test kits are inexpensive, simple to use, and take the guesswork out of knowing whether the soil needs amending. If the reading shows a pH below 6.5, adjustments will need to be made for growing lavender.
Grow in Pots
Container gardening gives you full control over the soil environment. You can create an ideal potting mix for lavender by blending basic potting soil with lime to raise the pH and sand or perlite to improve drainage. Aim for a mix with a neutral pH around 7.
Use containers at least 12-16 inches wide to give lavender’s roots ample room. Place in full sun.
Use Raised Beds
Like containers, raised beds allow you to customize the soil blend. Fill your raised bed with a mix of potting soil compost, horticultural sand and lime. Test the pH – it should be at least 6.5 for lavender. situating lavender in a raised bed improves drainage.
Amend Garden Soil
For in-ground planting, thoroughly mix lime or wood ash into the top 6-12 inches of soil to raise the pH at least 3-6 months before planting. Re-test the soil pH periodically and add more lime if needed to reach the proper range.
When amending large areas, follow package instructions carefully to avoid making the soil too alkaline. It takes time for lime to fully integrate in the soil.
Choose Alkaline Mulch
Mulch helps regulate soil moisture and temperature. Alkaline mulch choices like crushed eggshells, wood chips, gravel, and pebbles can also gradually raise acidic soil pH for plants like lavender.
Provide Good Drainage
Excess moisture is detrimental to lavender roots, causing rot. Ensure proper drainage by planting on mounds or sloped areas. Mixing sand, pebbles, or perlite into soil also improves drainage.
Give Sun and Space
Lavender thrives in full sun and needs good air circulation. Allow at least 12-24 inches between plants. Crowding causes humidity and disease problems.
Water Sparingly
Lavender is highly drought tolerant once established. Water only when the top few inches of soil become dry. Proper drainage and infrequent watering prevent root rot issues.
Use Alkaline Fertilizer
Choose a balanced organic fertilizer formulated for acid-loving plants. Alternatives like wood ash or lime can provide nutrients while maintaining ideal soil pH for lavender.
Protect from Winter Wetness
Too much winter moisture is lavender’s nemesis Improve drainage and airflow by pruning plants in fall. Mulch with evergreen boughs to keep soil drier Avoid fertilizing late in the year.
Choose Adapted Varieties
English lavenders are more hardy and adaptable to marginal conditions than French or Spanish types. Varieties like ‘Munstead’ and ‘Hidcote’ tolerate more acidity than tender types like Lavandula stoechas.
Monitor Soil pH
Test soil pH yearly to ensure it stays in the optimal neutral to mildly alkaline range as you grow and care for your lavender. Adjust as needed to maintain the proper balance.
While lavender prefers alkaline soil, with careful attention to drainage, soil amendments, and growing conditions, it can thrive in less than ideal acidic soil. Containers and raised beds offer the most control over creating the perfect soil environment. But with initial preparation and ongoing care, in-ground lavender can succeed in amended garden soil.
Armed with the right information, you can have gorgeous, fragrant lavender even if your native soil is on the acidic side. Pay attention to proper soil pH, drainage, sunlight, spacing, and watering and you can overcome the challenges of growing lavender in acidic soil. With a little effort, you’ll reap bountiful blossoms and have happy, healthy lavender plants for years to come.
How to Grow Lavender in Clay Soil
One of the worst things that can happen to lavender is that its roots will rot if it sits in wet soil, and clay soils usually drain slowly. However, you can make your clay soil better for growing lavender by mixing in gravel, sand, and a small amount of organic matter. This will make the soil nice and draining.
Also, planting your lavender in a mound can help keep it above the level of the rest of your garden. This way, if the area gets too wet, your lavender might at least be able to escape the worst of it.
5 Tips to Grow Perfect Lavender
FAQ
Can lavender tolerate acidic soil?
What is the best fertilizer for lavender?
How to make soil more alkaline for lavender?
What kind of soil is best for lavender?
Can lavender grow in acidic soil?
If your soil is between pH 6.5 and 7 (slightly acidic to neutral) lavender can still grow very well, without problems. Lavender only really starts to show signs of stress (poor growth, fewer flowers) when the soil acidity is below pH 6.5. However, if you do have acidic soil and want to grow lavenders then your three most practical options are:
What is a good soil pH for lavender?
Slightly alkaline: Lavender prefers a slightly alkaline soil with a pH level between 6.5 and 7.5. Acidic soils with a pH below 6 can inhibit the plant’s ability to absorb nutrients from the soil, leading to stunted growth and poor health.
What soil do lavender plants need?
However, there are a few things you need to know about the soil requirements of lavender plants to ensure their success. First, lavender plants prefer slightly alkaline soil with a six- and eight pH. If your soil is too acidic, you should add lime to it to raise the pH.
Does Lavender Love alkaline soil?
Lavender’s love for alkaline soils is no secret, but getting that pH just right can be a bit of a balancing act. If your soil is more acidic than a cup of black coffee, it’s time to sweeten the deal. Testing your soil’s pH is the first step—think of it as a soil selfie, giving you a glimpse of its current mood.