Avoid These 6 Common Lavender Growing Mistakes for Success

When planted correctly and cared for, lavender can flourish for years. However, it can quickly decline if its needs aren't met.

With its gray-green foliage, vibrant pink and purple blooms, and beloved fragrance, lavender stands out as a popular shrub. This herb has been cherished for its culinary and ornamental value for ages, making it a staple for many gardeners.

From my personal experience of cultivating lavender, I've learned about several frequent pitfalls that can hinder its growth.

6 Common Lavender Growing Mistakes You Should Avoid

Here are the six primary mistakes that can lead to lavender plants struggling, along with my advice on how to prevent them to ensure your herb garden thrives.

1. Selecting the Wrong Variety

Despite its Mediterranean origins, lavender adapts to US hardiness zones 4-10. However, different varieties have varying tolerances to frost, heat, and humidity, which can affect their health. Choosing the right type for your environment is crucial.

Some varieties, like English lavender, can survive winter temperatures as low as -20˚F, while others may only endure down to 20˚F or 30˚F. You may need to winterize lavender during dormancy to protect it from harsh conditions.

There are three primary types of lavender to consider:

• English lavender: Cultivars of Lavandula angustifolia showcase narrow, aromatic flowerheads in shades from deep purple to soft mauve. These resilient varieties can thrive in zones 5-8. Gardeners in northern areas might need to insulate roots with mulch and use frost protection measures, such as fleece, during severe winters, especially when forecasts predict extreme weather.
• French/Spanish lavender: Lavandula stoechas features distinctive 'tufts' of petals atop elongated flower heads. These types are less hardy and best suited for gravel gardens or container gardening, flourishing in zones 7 and above, with summer blooms lasting into fall.
• Hybrid lavenders: Lavandins are a cross between English varieties, cultivated extensively in southern France for their robust fragrance and oils, commonly used in perfumery. They thrive in hardiness zones 5-10.

2. Overwatering Lavender

Native to the Mediterranean, lavender flourishes in dry, poor soil. Although it's stunning and aromatic, it requires minimal watering. In fact, excessive moisture can lead to root rot, endangering the plant's survival.

Consider the soil type when planting lavender. It thrives in well-draining, gritty soil. If your garden has clay, dig a hole two to three times larger than the root ball and loosen the sides and base with a fork to enhance drainage.

Failing to do so can trap water, leading to root rot and inviting additional pests and issues. Before planting in heavy soil, mix in compost like Ribbons Organic Compost and gritty material like Garden Pumice from Amazon to improve drainage and keep roots healthy.

If space is limited, consider growing lavender in containers or herb planters.

3. Overfertilizing Lavender

Excessive fertilization can be just as detrimental as overwatering, contributing to plant issues.

Like many Mediterranean herbs, lavender thrives in low-nutrient, dry soil. Over-fertilizing, particularly with nitrogen-rich products, can result in lush foliage but few blossoms.

This soft growth is prone to diseases like powdery mildew, as dense stems impede airflow, making plants more vulnerable to pests.

4. Planting in Shade

Lavender is adapted to sunny Mediterranean climates, so it needs full sun for optimal growth. Aim for 8-10 hours of sunlight daily; plants grown in shade will have weaker fragrance.

When planting, ensure lavenders have ample space to grow without being overshadowed by larger plants. If you're unsure where to plant, try sun-mapping to identify the sunniest spots in your garden.

Ideal locations include south-facing areas, gravel gardens, or mixed borders with sun-loving companions. If you need to relocate your lavender, spring or fall, when the soil is moist and warm, is the best time. Older, woody plants may not transplant well, so consider taking cuttings to propagate new plants for better conditions.

5. Overcrowding Plants

Lavender can grow quite large and needs sufficient space to thrive. Planting them too close together increases the risk of fungal diseases due to limited airflow, as well as pest infestations.

Even though lavenders prefer poor soil, crowded plants will compete for water, nutrients, and light, hindering healthy growth.

Lavender can be purchased as small plugs or larger plants. The best planting time is April and May, when the soil benefits from spring moisture. In a flower bed, space them 3 feet apart; for hedging, 1 foot apart will suffice. For container growing, use well-draining potting soil mixed with horticultural grit to boost drainage.

6. Improper Pruning

Once established, lavender requires annual pruning. The approach varies depending on the plant type and age. Correct pruning results in healthy, attractive mounds with ample blooms, while incorrect techniques can lead to unattractive, woody plants with reduced flowering.

Smaller bushes can be pruned with scissors, such as this affordable four-pack of Kotto tools, while larger shrubs benefit from shears like these Gardena hedge shears.

Ensure your tools are sharp to prevent damaging the stems, and make sure to clean them properly after each use.

One of the advantages of growing lavender is learning to harvest its flowers for drying, perfect for potpourri, floral arrangements, or even cake decorations.

By steering clear of common harvesting mistakes and timing it right, you'll discover the many uses of this well-loved plant.