How To Grow Borage
Borage (Borage officinalis), is a versatile annual herb that is very easy to grow. The leaves and stems are covered with fine bristly hairs. It produces star-shaped vivid blue flowers midsummer. Its culinary uses are numerous. The flowers, stems and leaves are all edible. The flowers can be used fresh or candied. The stems and leaves with their cucumber like flavor can be steamed.
Growing the Herb Borage
Borage should be started outside 1 – 2 weeks prior to the last frost. It can be planted anytime in a mild climate. Plant in full sun at a depth of around ¼-inch. Seeds should be planted in groups of 3 to 4, spaced 15 inches (38cm) apart. Seedlings should appear in approximately 5 – 10 days. When they reach a height of 2 inches tall, thin back to 1 seedling every 15 inches. Borage occupies a lot of room once it matures. The herb readily reseeds itself, however, sometimes borage does not flower the first year. Borage can be biennial.
Borage is best planted outdoors sown directly in soil after danger of the last frost, as it does not transplant well. Borage can also be planted in containers indoors or outdoors.
Borage grows to a height between 2 and 3 feet tall (60cm – 90cm).
Borage should be planted 15 inches (38cm) apart.
Preferred pH Range
Borage will grow in a wide pH range between 4.5 (very acidic) and 8.5 (very alkaline) with an ideal pH of around 6.5.
From seed. Direct sow outdoors in spring after danger of frost has past. Do not plant seeds deeper than 1/4-inch. Will often reseed naturally.
Seed Germination Period
Borage seeds will germinate in soil in approximately 5 to 10 days when the soil temperature is at 70 degrees F.
Number of Seeds per Gram
There are approximately 65 to 70 borage seeds per gram.
Borage will grow in just about any type of soil as long as it’s prepared properly. Turn soil over to loosen and aerate. For optimum growth add compost. Rich, moist and light soil is the best.
Alternative Growing Media
Soilless potting mixes (Pro-Mix, Sunshine Mix, etc.), perlite, vermiculite, rockwool, coco peat.
Sun & Lighting Requirements
Borage grown outdoors prefers full sun for the best growth but will tolerate some shade. It is not recommended to start borage indoors for transplanting.
Borage will grow indoors satisfactorily under high output T5 fluorescent plant grow lights, compact fluorescent, or high intensity discharge (metal halide or high pressure sodium) plant growing lights.
Keep high output and compact fluorescents approximately one foot above the plants, and HID lights between 2 and 4 feet above the plants, depending on wattage.
Have an oscillating fan gently stir seedlings for at least 2 hours per day to stimulate a more compact, and sturdier plant habit.
Annual. Not applicable.
Keep the soil moist. You can apply mulch to help keep the soil moist.
Potential Plant Pests and Diseases
Borage is relatively disease and insect free. The plants can be affected by Japanese beetles, springtails and wheat bugs. Aphids can also be a problem.
Borage is beneficial to almost everything it is planted near, especially strawberries, cucumbers, gourds, tomatoes, and cabbage. It attracts predatory insects and honeybees while repelling many insect pests. Borage is known as the "magic bullet of companion plants".
Borage is deer resistant.
Buy Borage Seeds by Botanical Interests
Heirloom Organic Borage Seeds
An easy-to-grow and versatile herb in the garden and kitchen that attracts beneficial insects and bees.