Native to the Mediterranean region, rosemary has silvery needle-like foliage and delicate flowers. It complements meats and vegetables, brings its unique, piney flavor to breads, and blends well with other herbs!
How to Sow
Rosemary may be grown from seed sown early indoors and transplanted outside after frost, or planted as a potted plant.
Sowing Seed Indoors:
- Sow rosemary seeds indoors 10 weeks before outdoor planting date in spring using a seed starting kit
- Sow seeds ¼ inch deep in seed starting formula
- Keep the soil moist at 70 degrees F
- Seedlings will emerge in 14-21 days
- As soon as the seedlings emerge, provide plenty of light on a sunny windowsill, or grow seedlings 3-4 inches beneath fluorescent plant lights turned on 16 hours per day, off for 8 hours at night. Raise the lights as the plants grow taller. Incandescent bulbs will not work for this process because they will get too hot. Most plants require a dark period to grow, do not leave lights on for 24 hours.
- Seedlings do not need much fertilizer, feed when they are 3-4 weeks old using a starter solution (half strength of a complete indoor houseplant food) according to manufacturer’s directions.
- If you are growing in small cells, you may need to transplant the seedlings to 3 or 4 inch pots when seedlings have at least 2 pairs of true leaves before transplanting to the garden so they have enough room to develop strong roots
- Before planting in the garden, seedling plants need to be “hardened off”. Accustom young plants to outdoor conditions by moving them to a sheltered place outside for a week. Be sure to protect them from wind and hot sun at first. If frost threatens at night, cover or bring containers indoors, then take them out again in the morning. This hardening off process toughens the plant’s cell structure and reduces transplant shock and scalding.
Planting in the Garden:
- Select a location in full sun where water drains quickly after a rainfall.
- Prepare the bed by turning the soil under to a depth of 8 inches. Level with a rake to remove clumps of grass and stones.
- Dig a hole for each plant large enough to amply accommodate the root ball.
- Carefully remove the plant from its pot and gently loosen the root ball with your hands to encourage good root development.
- Place the top of the root ball even with the level of the surrounding soil. Fill with soil to the top of the root ball. Press soil down firmly with your hand leaving a slight depression around the plant to hold water.
- Use the plant tag as a location marker.
- Water thoroughly, so that a puddle forms in the saucer you have created. This settles the plants in, drives out air pockets and results in good root-to-soil contact.
- Rosemary may also be grown in containers. Make sure the potting mix is light and well drained. Use a mix for succulent plants, or add perlite to improve drainage.
- Do not allow plants to dry out, but never let the soil stay wet. A clay pot is recommended as it drains well.
How to Grow
- Keep weeds under control during the growing season. Weeds compete with plants for water, space and nutrients, so control them by either cultivating often or use a mulch to prevent their seeds from germinating.
- Mulches also help retain soil moisture and maintain even soil temperatures. For herbs, an organic mulch of aged bark or shredded leaves lends a natural look to the bed and will improve the soil as it breaks down in time. Always keep mulches off a plant's stems to prevent possible rot.
- Keep plants well-watered during the growing season, especially during dry spells. Plants need about 1 inch of rain per week during the growing season. It's best to water with a drip or trickle system that delivers water at low pressure at the soil level. If you water with overhead sprinklers, water early in the day so the foliage has time to dry off before evening, to minimize disease problems. Keep the soil moist but not saturated. Rosemary is particularly susceptible to root rot, avoid overwatering, and make sure the soil drains well. Rosemary does benefit from misting in dry conditions.
- Rosemary requires little care, but can benefit from occasional pruning. Pinch the stems to encourage bushiness or remove the branches to attain a desired shape.
- Silver foliaged herbs prefer poor, well-drained soils and little fertilization.
- Monitor for pests and diseases. Check with your local Cooperative Extension Service for pest controls recommended for your area.
- Rosemary is marginally hardy in zone 7 and many gardeners bring their plants inside during the winter.
Harvest and Preserving Tips
- Clip leaves or stem tips as needed. Rosemary may be used dry or fresh.
- If you are using rosemary fresh, pick it early in the morning for highest oil content.
- For drying or freezing, harvest leaves that have their maximum oil content, just before flowering.
- Harvest leaves, tips and flowers. Chop or crumble leaves before using.
- To dry, cut whole stems on a dry morning. Tie stems loosely together in small bunches and hang in a dry, airy location out of the sun. Rosemary may also be dried on a cheesecloth or a window screen in a dry, shady location. Do not use heat to dry rosemary as the fragrant oils can be volatile. When thoroughly dry, store in a tightly sealed glass jar in a dry, dark location.
- Rosemary may also be frozen dry or in an ice cube tray in water or olive oil.