Raphanus sativus - sow outdoors, germination in less than two weeks at 50ºF,

Ratibida columnifera - use 9 weeks at 39ºF, move to 80ºF for germinationnation.

Ratibida pinnata - use 9 weeks at 39ºF, move to 80ºF for germination.

Reseda odorata - germination in less than two weeks at 68ºF,

Rheum australe - Very lightly cover seeds and use F 70, germination in 2 to 4 weeks.

Rheum palmatum 'Atrosanguineum' - Very lightly cover seeds and use F 70, germination in 2 to 4 weeks.

Rheum palmatum V. tanguticum - Very lightly cover seeds and use F 70, germination in 2 to 4 weeks.

Rheum palmatum - Germination in 2weeks at 68ºF.

Rhodochiton atrosanguineum - Germination over many weeks at 60ºF, slow germination that is spread out over a few months..

Rhus chinensis - nick and soak, 3-4 weeks at 68ºF . Surface sow seeds, light needed for best results., if no germination., 2-4 weeks at 39ºF, then 68ºF

Rhus typhina - nick and soak, 3-4 weeks at 68ºF . Surface sow seeds, light needed for best results., if no germination., 2-4 weeks at 39ºF, then 68ºF

Rhus typhina 'laciniata' - nick and soak, 3-4 weeks at 68ºF . Surface sow seeds, light needed for best results., if no germination., 2-4 weeks at 39ºF, then 68ºF

Rhynchosia phaseoloides - nick coat, germination in less than two weeks at 77ºF,

Ricinus communis 'carmencita' - soak seed, germination in less than two weeks at 60ºF,

Rosa blanda - Put seeds is a plastic baggy with moist seed mix and put in fridge for 120 days. Remove and sow at 65-70F.

Rose "Angel Wings' - Sow seeds into a bag with some moist seed medium and put in the fridge for 3 weeks, So and use F 65. germination in 2-6 weeks.

Rosmarinus officinalis - germination in less than two weeks at 68ºF . Surface sow seeds, light needed for best results.,