- 1). Prepare the planting site by mixing a rich compost into the soil. You can purchase compost at a gardening supply store or make your own. Mix in about 2 cups per square foot of garden. The ideal soil pH for borage is 6.0 to 7.0. Borage plants prefer slightly sandy soil; add 1 cup of sand per square foot of garden if necessary.
- 2). Purchase borage seeds online or at a gardening supply store. Sow the borage seeds by making several straight furrows in the soil. Place the seeds in the soil in short lines. Cover seeds with about 1/4 inch of soil. For a more wild appearance, scatter the seeds all over the garden bed. The seeds can also be planted in large pots the same way.
- 3). Water the seeds regularly every three to four days. When the shoots pop up, they will need to be thinned. Borage plants eventually have about a 12 inch circumference, and so the plants should be thinned to leave at least 12 inches of space from any other plants. The seedlings that are removed can be planted elsewhere or discarded.
- 4). Replant new seeds every four to six weeks. That will keep up the supply if you use the borage leaves for medicinal or herbal purposes. Alternatively, you can wait for the plants to go to seed and re-propagate on their own. Protect the plants from harsh winds, as the delicate root systems can easily be torn up by heavy gusts.
- 5). Borage plants need lots of sun, so plant in beds that get plenty of sunlight or place pots in sunny places.
Because borage is such a hardy plant, fertilization is not necessary. The plants will grow excellently on their own.