Rosemary

When should I plant
Plant rosemary seeds indoors 8-10 weeks before the last frost, cold stratifying them to help with sprouting, then transplant after frost. Sow seeds shallowly in well-draining soil, provide warmth and light, and keep moist but not soggy, as they're slow to germinate and require good drainage and sunlight.

Site consideration
Choose a site with full sun (6-8 hours) and excellent drainage, ideally sandy/loamy soil, avoiding heavy clay; ensure good air circulation and don't overwater, as it's drought-tolerant once established, but needs consistent moisture until germination. Indoors, sow seeds in pots with sterile, well-draining mix, keeping moist and covering lightly, as seeds need light to sprout.

Water
Lightly mist the soil with water, ensuring that it is moist but not soggy. Using a spray bottle can help maintain even moisture without flooding the seeds. Rosemary prefers dry conditions, so allow the top layer of soil to dry out between waterings. Established rosemary plants are drought-tolerant. Water them only when the soil feels dry, as overwatering can lead to root rot.

Sunlight
Choose a location with full sun exposure for best results. Rosemary needs at least 6–8 hours of sunlight daily, which encourages bushy, healthy growth.

Seed Germination
Rosemary seed germination is slow and challenging, needing warmth (65-80°F), consistent moisture, and light, with seeds pressed onto a well-drained mix and not covered, often aided by heat mats and humidity domes for 14-28 days to overcome low germination rates. Start indoors 10-12 weeks before the last frost for best results, keeping conditions warm and bright until seedlings are sturdy enough to transplant.

Transplant
Transplanting rosemary seedlings when they have 4 true leaves, after starting indoors 10-12 weeks before the last frost. Transplant to individual pots when ready, and then harden them off before planting outside after frost danger has passed. Space them well in full sun and well-drained soil.

Other Elements
Fertilization
Rosemary doesn’t need heavy fertilization; start with compost or worm castings in rich soil, then use a weak, balanced liquid fertilizer (like half-strength) or organic feed once seedlings are a few inches tall (around 6-8 weeks), applying sparingly in spring/summer and withholding in fall/winter to keep it hardy.

Weed control
Use physical barriers like mulch (cardboard/newspaper) or weed fabric covered with gravel, plant ground cover to smother weeds, or do manual hand-weeding before weeds seed, keeping in mind rosemary's need for sun, well-drained soil, and minimal competition from aggressive plants like mint.

Harvest
Snip the tender, green tips (2-3 inches for fresh use, up to 8 inches for drying) from the outer branches using clean shears, cutting just above a leaf node to encourage bushier growth, and avoid cutting more than a third of the plant at once, always skipping the woody base. For larger amounts, you can trace a stem back to its base and cut it off to shape the bush.

Seed Storage
The seeds will maintain a high germination percentage if stored under proper conditions. How long your seeds remain viable will depend on the temperature and moisture levels the seeds are exposed to. Seeds which are improperly stored will quickly deteriorate if unprotected against high humidity and dramatic temperature fluctuations day after day.

For best results, keep the seed in our moisture-proof ziplock sealing bags, which provide a better moisture prevention effect. Glass jar or plastic containers with snap-on lids works well too, add a packet of desiccant before sealing into the seed, such as silica gel to remove any moisture remains in the storage container. Seed stored under these conditions will remain viable for as long as years.

Factors Which commonly Cause Poor Results
  1. Improper drainage soil
  2. Sowing depth more than one inch
  3. Covering the seed too deep beneath the soil surface
  4. Cover a large area with a small amount of seed.
  5. Plant at a wrong time of a year
  6. Lack of sunlight
  7. Inadequate rainfall after seed germination. The area should not be allowed to become completely dry. Supplemental watering may be required to sustain plant life.
  8. Extreme weather conditions: hail, drought, excessive rainfall, floods, unseasonably cold temperatures.

 

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