I need some advice on growing Rosemary from seed. I understand it has a very low germination rate, but I am up for the challenge. Any one had a positive experience growing from seed? any tips you can share?
rosemary from seed
Sorry, no ideas here. I need the hardier cultivars, so I'm pretty sure that means buying plants or propagating from cuttings for me rather than growing from seed.
Rosemary is an herb in the labiatae (mint) family. It's a tender perennial grayish green ornamental shrub 2-6 feet high with scaly bark (as it grows bigger.) It's foliage is needle-like and gray green in color. Flowers are small pale blue to pink clusters.
Direct seeding is not always successful. Start seeds indoors and transplant the seedlings out. Darkness will aid germination. Cover the seeds lightly with soil after sowing. Optimum soil temperature for germination is 60º Fahrenheit. Germination time is usually 14-21 days. Sow heavily because the seeds have a poor germination rate. Some seeds can germinate up to 3 months after sowing. Rosemary needs full sun to partial shade, and a well drained area. Water in between dry downs; do not use enclosed planters. Their roots dislike being cramped up.
Use critterologist's Clump transplanting & seed starting tips for this in the Propagation Forum: http://davesgarden.com/forums/t/589725/
You can take 4" cuttings from a plant and strip the lower leaves off & save those leaves for seasoning; then put the cuttings directly into a well drained spot to keep it from getting root rot. It is recommended to take 4" cuttings when harvesting-which can be done anytime of the year.
During the winter, temperatures must remain above 10º Fahrenheit for outdoor plants.
We bring our Rosemary indoors for the winter up here because it can be too cold for the plants to survive outdoors, -20º Fahrenheit up here. This herb needs particular care to survive the winter though. It's only hardy to Zone 7a; but you may be able to get away with it outdoors if you mulch the plant heavily. But I'd take some cuttings in for the winter too if I were you.
You'll need to transplant it carefully in to a large container so it has room to grow. The roots tend to be tough, (like the shrubs they are) 3-4 feet some times; so when digging up; dig wide and deep. Use a good household potting soil mix and organic compost (not too much if it is a moist variety --this will be too strong in a pot and may contribute to root rot). Make sure it is well drained, well watered and spray the leaves with water every so often, especially if you have the heat up in the winter.
~* Robin
Thanks Robin, I appreciate the info. I would do cuttings, but don't currently have a rosemary plant, so thought I would try seeds. Sounds like I need cooler temps to do seeds though, will need to wait till fall, sounds like chilling in the frig is not an option, that would be too cold.
I have had rosemary in containers so it could be brought in, always managed to kill it after a couple years. In reading your post, I think maybe it was too root bound and resented that. I am willing to try once more, I think it is worth the effort, such a lovely fragrant plant.
Jan, there are rosemary varieties like 'Arp' that should be hardy in your zone. You can also help them overwinter by planting them in a raised spot (to be certain of good drainage), and by providing something as a heat sink to moderate temperatures (a wall, big rocks, cinder blocks around them). I finally had one overwinter last year this way. I also have a slightly more tender one (from my MIL in NC) in a big pot that I do bring in every winter, and it has survived for several years -- I'm not sure why, as I've always killed rosemary indoors before this plant.
There was a recent thread on rosemary that might be helpful, http://davesgarden.com/forums/t/609723/