How to Plant Rose Seeds? Latest Planting Method Explained in Detail
Usually roses are generally propagated by cuttings, and growing them from seeds is very rare. First, because the seed germination rate is low; second, because seed propagation leads to degeneration; third, because seeds are not easy to obtain. However, no matter how difficult it is, that does not mean it is impossible. Propagating roses from seeds is suitable for breeding new rose varieties. Let's take a look below at how to plant rose seeds.
What characteristics do rose seeds have?
Rose seeds have a dormant characteristic. Generally, there are three reasons for plant seed dormancy:
1. The seed coat is hard, which restricts water absorption and respiratory metabolism.
2. The embryo is not fully developed and must undergo after-ripening before it can germinate.
3. The presence of certain inhibitors inhibits seed germination.
The reason for rose seed dormancy is caused by ABA (abscisic acid) contained in the pericarp and seed coat. This is the result determined by high performance liquid chromatography (HPLC). The pericarp, seed coat and embryo of rose seeds all contain ABA. Through tissue culture methods, it has been confirmed that the relatively high level of ABA contained in the pericarp and seed coat is the main cause of seed dormancy. The amount of ABA contained in the embryo is extremely small and is not enough to cause seed dormancy.
Pre-sowing treatment of rose seeds
Due to the above characteristics of rose seeds, newly harvested seeds cannot germinate. Before sowing, they must undergo “sand stratification” treatment before they can germinate and emerge. That is, mix the seeds into moist sand, place them in a container, cover with 3-5 cm of moist sand, and keep them at 0-2°C for 60-90 days, then sow them.
Sowing methods for rose seeds
Sowing should be carried out at 5-10°C. You can use dibbling, broadcasting, drilling or pot sowing, with a spacing of 3 cm. After sowing, cover with a 1 cm layer of vermiculite or plain sand. Under normal circumstances, seedlings can emerge about 40 days after sowing.
Precautions for propagating roses from seeds
1. Generally around November, cut off the mature fruits whose pericarp has turned yellow and red, and store them in moist sandy soil at 0-6 degrees. In January or February of the following year, select seeds and prepare them for germination forcing. Put the pre-selected plump seeds into a plastic bag filled with moist sandy soil, fine wood shavings or vermiculite, tie the bag tightly, and place it in a dark environment with freezing nights and thawing days and sharply changing temperatures. As the temperature rises, check once a week and carefully pick out the seeds that have cracked and shown white.
2. Plant the cracked seeds that have undergone germination forcing carefully in the seedbed at a plant and row spacing of 3 cm * 5 cm. The lower part of the seedbed can use river sand or garden soil, with a thin layer of vermiculite (or fine wood shavings) spread on top. Place the germinated seeds on it, then carefully cover with a layer of sandy soil about 1 cm thick, and finally spray thoroughly with water using a watering can.
3. Note that the sowing soil must be disinfected and insect-killed. The seedbed is best arranged inside a greenhouse, and at the same time cover the arched shed well with plastic film, keep the seedbed moist frequently, and maintain a suitable germination and seedling temperature of about 20 degrees. When the seeds emerge and grow 3 to 5 leaves, promptly move them to small flower pots to promote the growth of the seedlings. To promote rapid growth of the seedlings, the potting soil should remain loose, and it is advisable to apply thin fertilizer frequently, expose them to more sunlight, but do not water too much, so as to avoid inducing diseases.