as mentioned when I replied to Mick, the powder with be a fungicide as we’re trying to help prevent dampening off – although careful watering is always the best solution to this problem. The hydrogen peroxide mentioned in the blog will be the same as the hair bleach and is just an extra precaution taken by the author to sterilise her seeds. Using normal bleach in tiny quantities is usual practice in preventing harmful bacteria in seed processes, especially if they are prone to disease in the first place.

Roses are flowering perennial plants prized for their beautiful flowers, which are made up of delicate and layered petals. One of the best ways to propagate new roses is to take a cutting from an existing plant and grow it into a whole new rose bush. When you grow roses from a cutting, you cut a stem from a healthy plant and root it in a growing medium so it grows into an independent plant of its own. However, you can also propagate roses by dividing an existing plant, but this requires a little more effort than with cuttings. To propagate by division, you have to dig up an entire rose bush, cut the root system in half, and replant the two halves as separate bushes.
Be aware of your variety’s needs. Rose care will depend a lot on the variety you’re raising. Some roses like William Baffin and Lady Hillingdon climbing roses are more drought tolerant, for example, while others need more water. Some varieties can withstand less sunlight than others. Rose varieties should also be pruned differently depending on the variety and your climate area.
Black Spot: Rose plant leaves with black spots that eventually turn yellow have black spot. This is often caused by water splashing on leaves, especially in rainy weather. Leaves may require a protective fungicide coating, which would start in the summer before leaf spots started until first frost. Thoroughly clean up debris in the fall, and prune out all diseased canes.