Despite their reputation for being finicky, most roses are simple to grow and easy to propagate at home. “Propagate" simply means to reproduce a plant easily from a simple cutting. Unlike seeds, which produce very different plants, rooted cuttings produce replicas of their parent. You don't have to be a trained rosarian to reproduce treasured family heirlooms or favorite garden roses.
Water the planted rose seeds well and place them outside in direct sunlight (no need for Grow Lights). If there is still danger of frost, then you will need to place the seed trays in a protected location such as under a tree or patio. You will need to keep the rose seed trays watered and don't let them dry out. After about six weeks, or when the weather starts to warm up, the little rose seedlings will start to sprout. They will continue to sprout as long as the weather is cool, but will stop sprouting when it gets too hot.
When you transplant your roses, be sure to dig a much bigger hole than you think you need (for most types, the planting hole should be about 15 to 18 inches wide), and add plenty of organic matter such as compost or aged manure. This will feed your plant in the years ahead. Some old-timers recommend placing a 4-inch square of gypsum wallboard and a 16-penny nail in the hole to provide calcium and iron, both appreciated by roses.
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.
Growing roses from seeds is not the fastest method for propagating roses but has several advantages. Roses from seeds take a little longer but then you end up developing a new set of varieties. Professional hybridisers select a new line of easy to grow and disease resistant rose to propagate. However, for you, each seedling will be a surprise when they finally bloom. It is like opening your birthday present when you were a kid. You never really knew what to expect! That is the same feeling seeing those little seedlings opens up for the first time.
Prepare a pot. Fill the small pot with potting soil. For the best results, replace a quarter of the soil with perlite, peat moss, or vermiculite, or a combination thereof. This will increase air flow and draining, giving your cutting a better opportunity to root. If the soil is dry, water it and allow the excess water to drain out, so that the soil is evenly moist.
Selecting a disease-resistant rose is the single most effective way to avoid problems and the need for chemicals. You might start by considering some of the old rose varieties, many of which have natural disease resistance. You can also look to many of the modern roses, which are now being bred for improved disease resistance. Hybrid teas are notoriously disease-prone, and seem to lure every insect pest from miles around. They can be difficult to grow without an arsenal of chemical dusts and sprays.
Tracing the history of a particular rose can be a fascinating adventure, but it is hardly an exact science. The old roses have cross-bred so many times, and so many varieties have been lost to time, that it is often impossible to uncover the exact parentage. If you are one of the many who become possessed by roses, you may eventually find it important to know the difference between a gallica and a Bourbon. But until that point, our advice is not to worry about it. The important thing is to select a rose that you find beautiful, and that suits your garden.
This is a fungus called black spot. Left untreated, it can cause all the leaves on your roses to turn yellow and fall off. It will also affect nearby plants, as it spreads by spores. Remove ALL INFECTED material and throw it away or burn it. Do NOT leave it on the ground as this fungus is very hardy. It can survive winter and travels very easily, even after being removed from the affected plant. Spray your plants regularly (bi-weekly) in the growing season with a good fungicide (I like the Bayer products). You can also add a little bit of dish soap and baking soda to a spray bottle with water and spray the entire plant.