The Best Soil for Lavender

Soil pH

• Lavender needs alkaline soil with a pH between 6.4 and 8.2 to grow well. Determine the pH of your preferred planting site before you plant by performing a soil test on the sample. Acidic soils have a pH below 6.3. If you plant lavender in overly acidic soil, the plant eventually declines and dies. You can raise the pH to the desired alkalinity by adding agricultural lime and incorporating into the garden soil prior to planting. The soil test results provide a guide that details how much lime is necessary.

Soil Quality

• Avoid planting lavender in beds with rich soil. Lavender grows poorly in loam soils and those that contain large amounts of organic matter. Planting sites with high amounts of leaf litter or compost amendments are too rich to successfully grow lavender shrubs. The shrub thrives in well-drained, sandy soils. It cannot tolerate beds that retain too much moisture or drain poorly. If water collects on top the soil after irrigation, rain or snow melt, the soil drains too slowly and lavender will grow poorly.

Fertility

• Lavender requires minimal soil fertility for good growth. The shrub cannot tolerate too much fertility, whether from organic matter naturally present in the soil or from fertilizer applications. Lavender doesn't need fertilization before planting or throughout its lifespan. Avoid planting it in shared beds where nearby plants may require frequent fertilization, as the fertilizer run-off can damage the lavender bush. Use edging around specimen plantings so fertilization from nearby lawn areas doesn't penetrate into the lavender bed.

Soil Amendments

• The soil in lavender beds may benefit from some amendments that aid drainage as long as they don't provide too many organic nutrients. Coarsely shredded bark, quarter-inch bark nuggets or sawdust works well as a soil amendment due to its low nutrient content. Spread up to an inch of the amendment over the bed before you plant and work it into the top 6 inches of soil to improve the drainage of the site. Avoid sphagnum peat amendments; though this amendment provides excellent drainage, it makes the soil too acidic. Also avoid gravel and sand, as these materials tend to compact in the soil and prevent drainage.