In this blog post, I’ll show you how to grow borage, and share a simple recipe for making a liquid fertilizer using borage leaves that will give your plants the boost they need to thrive.
If you’re looking for an easy-to-grow herb that offers a wide range of benefits, borage is a great choice. This beautiful plant, also known as starflower, produces stunning blue-purple flowers and rich green leaves that can be used in a variety of culinary and medicinal applications. Not only is borage a lovely addition to any garden but it’s also packed with nutrients and has numerous health benefits.
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5 Tips for How to Grow and Use Borage
1. Learn the benefits of growing borage
Borage is a true champion when it comes to attracting bees and other beneficial pollinators to your garden. The plant’s beautiful blue-purple flowers are a magnet for bees, butterflies, and other flying insects, who are drawn to the nectar and pollen produced by the plant.
Because borage blooms for an extended period of time, it provides a consistent source of food for pollinators throughout the growing season.
This not only helps to support local bee populations, but it can also increase pollination rates in your garden, leading to bigger, healthier, and more abundant harvests.
Borage is often recommended as a companion plant for vegetables like tomatoes, squash, and peppers, which benefit from increased pollination rates.
Borage is also known for its numerous health benefits, making it a popular choice in herbal medicine. The plant is rich in essential fatty acids, including gamma-linolenic acid (GLA), which has been linked to numerous health benefits.
The leaves and flowers of borage also contain antioxidants, such as caffeic acid and rosmarinic acid, which can help to protect against oxidative stress and cellular damage. Additionally, borage has been used for centuries to soothe coughs, calm an upset stomach, and promote overall well-being.
2. Plant borage at the right time
When to plant borage:
Borage is a hardy, annual plant that is typically sown directly into the garden in the spring once the soil has warmed up and all danger of frost has passed. The ideal soil temperature for planting is 70°F.
In temperate regions, borage can also be planted in the fall, several weeks before the first expected frost, provided that there is sufficient time for the plant to become established before winter.
In the low desert of Arizona, plant borage seeds beginning in October and plant through January. Borage grows well until temperatures heat up in early summer.
3. Plant and care for borage correctly
How to plant borage:
- Borage has a long taproot and does best planted from seeds. Click here for 100% Heirloom, non-GMO borage seeds.
- Plant borage seeds ¼-½ inches deep, 12-18 inches apart. Keep the soil moist until the seeds sprout.
- Borage grows large, up to 3 feet tall and wide. Give plants plenty of room.
Where to plant borage:
- Borage grows best in full sun but will tolerate partial shade.
- For square-foot gardening, plant 1 borage per 2-3 square feet.
How to care for borage:
- Borage is a tough plant and can tolerate some neglect.
- Water borage well until plant is established. The more water borage receives, the larger the plant becomes.
- Borage does not require additional fertilizer.
- Borage reseeds easily. Each borage flower develops into several seeds; harvest flowers before seeds form to prevent reseeding. Save seeds to plant next season.
How to grow borage in containers:
- Borage has a long taproot and does best in at least 8 inches deep containers.
- Borage plants grow large; they grow best in their own container.
4. Harvest borage at the best time
- Harvest new leaves before bristles develop for the best flavor.
- Pick flowers as soon as they appear. Picking flowers often encourages more production.
- At the end of the season, leave a few flowers on the plant to save seeds.
- Borage leaves and flowers taste like cucumbers. Use them in drinks, salads, sandwiches, or desserts.
Learn more about growing and using edible flowers in this blog post.
5. Learn how to use borage – don’t let it go to waste!
How to use borage:
Chop up borage and use it as a chop-and-drop mulch.
Add borage to the compost pile at the end of the season; it makes excellent compost.
Use borage leaves to make liquid fertilizer (similar to comfrey). (See directions below)
Making a liquid fertilizer using borage leaves is a great way to give your plants a nutrient boost. Here’s a simple recipe to make your own:
Ingredients for fertilizer made with borage leaves:
- Borage leaves (enough to fill a quart-sized jar)
- Water
- Quart-sized jar with lid
Instructions for making fertilizer with borage leaves:
- Rinse the borage leaves in cold water to remove any dirt or debris.
- Chop the leaves into small pieces and add them to the quart-sized jar.
- Fill the jar with water, leaving about an inch of space at the top.
- Screw on the lid tightly and shake the jar vigorously to mix the ingredients.
- Place the jar in a dark, cool place (like a pantry) for two weeks. Shake the jar once a day to help distribute the nutrients in the leaves.
- After two weeks, strain the mixture through a fine mesh sieve or cheesecloth to remove the solids.
- Pour the liquid fertilizer into a bottle with a lid for storage.
How to use fertilizer made with borage leaves:
To use the fertilizer, dilute it with water at a ratio of 1:10 (one part fertilizer to ten parts water). Apply to the soil around the base of your plants every two weeks for optimal growth and health.
Note: Always test the fertilizer on a small area of your plants before applying it to your entire garden to ensure that your plants do not have an adverse reaction to it.
Read this post for more information about growing herbs in the low desert of Arizona.
- PLANTING GUIDE: Each month lists vegetables, fruit & herbs to plant outside & seeds to start indoors.
- HARVEST GUIDE: Photos show what may be ready to harvest that month.
- Planting dates are for the low desert of Arizona (zone 9b).
Sources for health benefits of borage:
- Prasad, K. (2015). Gamma-linolenic acid: an important ingredient in maintaining and restoring health. Prostaglandins, Leukotrienes and Essential Fatty Acids, 92, 1-15. doi: 10.1016/j.plefa.2014.10.002
- Ademiluyi, A. O. et al. (2018). Borage (Borago officinalis L.) leaves and flowers as potential sources of antioxidant compounds and minerals. Journal of Food Biochemistry, 42(4), e12541. doi: 10.1111/jfbc.12541
- Newall, C. A., Anderson, L. A., & Phillipson, J. D. (1996). Borage. Herbal Medicines: A Guide for Health-Care Professionals, 98-100. doi: 10.1177/00369330960310S309
If this post about how to grow and use borage was helpful, please share it:
Laura
Tuesday 24th of May 2022
I'm wondering what the best way is to harvest seeds? I've been picking the flowers and tossing them where I want them to grow. Do the flowers need to stay on the plant and dry out to produce seeds?
Sandy
Monday 3rd of April 2023
@Angela Judd, I just started focusing on medicinal herbs. Mullein might not survive our harsh heat but if there's a family member with asthma this should be on every gardener's grow list. The plant's ability to treat asthma & respiratory issues is exceptional.
Angela Judd
Tuesday 24th of May 2022
It's best to leave the flowers on the plant until they develop seeds. To harvest the seeds, pay attention to the blooms. When they die back if you look inside the blossom there will be a set of 3 seeds. Once they are completely ready, they drop, but you can often harvest them just before that.