How to Grow Year-Round Medicinal Herbs for Zone 9

Choose herbs according to climate requirements. Purchase varieties that thrive in dry, hot weather if you live in the desert Southwest. Pick those that withstand humid conditions in the Southeast. Select species such as yarrow, lemon balm, jasmine and rosemary, because these herbs flourish in zone 9.

Grow yarrow in hot and dry locations. Know that yarrow is considered a cold-hardy plant. Plant lemon balm and rosemary in zone 9 because this plant thrives in conditions that are both humid or dry. Grow jasmine in the dry to slightly moist conditions found in the southwestern areas of zone 9. Choose humidity-resistant species of jasmine, such as Asiatic jasmine for the Southeast.

Assemble your growing area. If you decide to plant in a container, plant to the depth of your pot if you decide to plant in a container. Dig a hole as big as the root ball of your herb and twice as wide. Grow yarrow and Asiatic jasmine in soil that contains a low acidity level. Choose various locations for lemon balm because this herb grows under most soil conditions. Plant rosemary in well-drained, sandy soil.

Use proper watering techniques for your herb garden. Water jasmine regularly during the time that the plant does its most growing. Ease up slightly during dormant periods. Water lemon balm once a week if you planted the herb in an outdoor garden. Water more frequently if you're growing the herb in a pot. Avoid adding moisture from above your yarrow plant because over-watering can cause flower damage along with spot formation on the leaves. Water yarrow from the ground, making sure it is kept slightly moist but not soaked. Water rosemary often, with light applications of moisture each time.

Add fertilizer, as needed, to specific medicinal herbs. Fertilize jasmine every four months with a fertilizer mixture that is one-tenth nitrogen, one-tenth potassium and one-fifth phosphorous (10-10-20). Fertilize lemon balm with 80 to 100 pounds of nitrogen, 100 pounds of phosphorous and 100 pounds of potash for every acre of lemon balm planted. Add a pound and a half of nitrogen to yarrow plants each spring. Use a second application in June if you have very sandy soil conditions in your garden. Avoid adding fertilizer to rosemary plants.