Lavender Fertilizer: Important Considerations & Best Options

If you consider using plant food and nutrients, a low nitrogen fertilizer formulated to encourage blooming is the most suitable lavender fertilizer option. However, a general-purpose fertilizer is also just as effective when diluted. The best time to fertilize lavender plants is annually during Spring and Summer.

Choosing the right formula fertilizer for your lavender is not the be-all and end-all of fertilizing. The plant’s success also depends on how often you fertilize and the most appropriate time to follow through with this process. Both over-fertilizing and under-fertilizing can have catastrophic results. Journey with me on this discovery process.

The Results Of Over Fertilizing A Lavender Plant

Often perception can vastly differ from reality; fertilizers are known to be the miracle food for all lavender plants. This perception remains a myth as it is not the sole contributing factor for the success of the growth of a lavender plant; the right soil mixture will challenge the use of the fertilizer at any given time.

Lavender plants prefer nutrient-poor soil. Too much fertilizer may cause the lavender to grow excess foliage and never flower, especially if the fertilizer is rich in nitrogen. A fertilizer rich in nitrogen can cause severe damage to the lavender plant, and the chances are it may not be able to survive the damage.

The lavender does not require much in the way of fertilization. Add more than a small amount of fertilizer, and you will be privy to watch masses of leafy growth. This growth is likely to droop as the flower spikes lengthen.

The University of California Cooperative Extension has extended a warning that too much fertilizer can endanger the health of these low-maintenance lavender plants. The appropriate question is, how often should you fertilize your lavender plant?

Lavender on white wooden background

When To Fertilize Your Lavender Plant?

There is often a gardening misconception that the more frequently you fertilize your plant, the healthier it will grow. Frequent fertilizing is not the requirement of lavender plants. The saying “a little goes a long way!” is a truth in the fertilization life of a lavender. 

If your lavender is flourishing in its environment without fertilizer, there is no need to add injury to success. Should you prefer fertilizing, Spring or Summer at the start of the growing season is the best time for fertilizing the lavender plant.

When Should You Stop Fertilizing Your Lavender Plant?

It would be wise to cease fertilization if you notice any signs of lavender stress, such as decreased blooming or foliage or diminished lavender scent. 

Over-fertilizing a lavender can harm the plant and put the plant under unnecessary stress. It is not advisable to fertilize this perennial in the fall, either. The fertilization will cause the plant to produce tender new growth that will only get damaged or killed in the winter.

Read more: Lavender Leaves Turning Yellow: 3 Likely Culprits & Effective Solutions

What Is The Best Lavender Fertilizer

An established mature lavender will rarely need fertilizer if it grows effectively and blooms abundantly. However, plants growing in deplorable soil conditions or pots may benefit from occasional fertilizer applications.

The lavender generally needs more nitrogen than phosphorus and potassium to flourish and give high yields for many years. However, the plant may respond well in some cases to nitrogen. Too much nitrogen favors foliage production with low oil content, so fertilized lavender plants are typically not suitable for extracting essential oils.

A high nitrogen-based fertilizer will favor the production of weeds.  A low nitrogen fertilizer formulated to encourage blooming is best, but general-purpose fertilizer will also work if it’s diluted.

Most gardening outlets would recommend a feed with a 7-9-5 or 15-15-15 fertilizer.  You can also feed your lavender with a small amount of slow-release fertilizer. They do not require more than a modest feed of fertilizer.

If you are cultivating lavenders, then a standard fertilizer scheme applied by many farmers involves adding 318 kg of N-P-K 20-10-10 per hectare every year (1 hectare = 2, 47 acres = 10.000 square meters). The quantity is often split into 2 or 3 applications, starting immediately after harvesting or pruning.

Organic lavender growers often add 8-10 tons of well-rotted manure per hectare and plow well before transplanting the young plants. They then follow-up with 5 – 6 tons of manure per hectare every 2-3 years, mostly during autumn.

Careful cultivation is crucial to not damage and protect the roots; irrigation after every manure application is also applied if there are no autumn rainfalls. You can also use slow-release fertilizer for hectares of lavender.

fertilizing lavender

Fertilizing Of Lavender Plants In Pots

Although many recommend that a lavender planted in a pot be fertilized every 14 days, this strategy does more harm than good. Hence they need to be fertilized in early Spring and again if needed in early Summer with an organic plant food listed for use in containers or a water-soluble liquid plant food at half the recommended strength found on the product label.

Fertilization of Lavender within a 14-day cycle would be too excessive; a mild re-fertilization twice a year is more than ample.  A lavender potted plant should be fertilized for the first time at the beginning of the growing season in June, the second time after the first flowering — with a bit of luck, you can stimulate the plant.

It is not suitable to use horn shavings, bark mulch, peat, and conventional flower fertilizers as these are not suitable for lavender because of their high nitrogen or acid content.

When planting lavender in pots, use a high-quality potting mix, such as Miracle-Gro® Performance Organics® All-Purpose Container Mix.

How To Fertilize Your Lavender Plant?

Place an inch (2.5 cm.) of good compost around the plant. This portion of compost should provide plenty of nutrients for the year to come. Start by diluting half a teaspoon of fertilizer in one gallon of water, apply to wet soil once monthly until late summer.

Also Check: Lavender Not Flowering? Most Likely Causes And 9 Solutions

Do Lavender Plants Need Fertilization?

True to its Mediterranean origin, a lavender thrives well in full sunlight and well-draining soil. There is no significant need for fertilization if the soil is rich in nutrients and has a combination of soil and gravel for good drainage.

Lavender plants do not benefit from mulching. It is better to leave the soil bare and dry in the original conditions they love! However, growing commercially lavender in today’s competitive landscape requires specific steps towards monitoring, improving, and enriching soil nutrients so that plants can give high yields for over 15 years. 

You cannot do universal fertilization as every lavender field has different needs. The performance of a soil analysis once a year is fundamental to diagnose nutrient deficiencies and take corrective actions. Only a handful of fertilizer is needed when you start.

Beyond that, feeding is not a requirement with these plants. Too much fertilizer can detract from the overall potency of your lavender.

Fertilization Of Lavender Growing In Flower Beds

Lavender Fertilizer fertilizer 1

Lavender planted in a flower bed does not require additional fertilizer. They form a dense and deep root system relatively quickly, a rooting system with which it can easily draw the few nutrients it needs. Over-fertilization can cause a lavender in the bed to lose its originality and density; this can even lead to complete withering.

A non-fertilized plant can survive winters much better. Restrained one-off fertilization can stimulate new branches if you have pruned an old lavender shrub to rejuvenate it after flowering.

Can Bone Meal Be Used For Lavender Plants?

Lavender is a lime-loving plant that yields best when there is a suitable dosage of calcium in the soil. Fertilizing with nitrogen might help with longer stems and full flower heads as the plant matures. Blood and bone meal are said to be beneficial as a nitrogen source.

Conclusion on Lavender Fertilizer

Lavender is indeed a low-maintenance plant. If placed in full sunlight and well-draining soil, this beauty will reward you with its fragrant aroma. The lavender plant is not solely dependent on fertilization for its survival. As long as the general care routine is followed, the plant will thrive. Just be mindful that you do not over-fertilize.