Caring for rose bushes is important to their overall health and vigor, especially when it comes to watering. Roses require at least an inch of water weekly throughout their growing season, beginning in spring or following spring planting. While overhead watering is suitable before the onset of new growth, it is often better to water these plants at the soil line using soaker hoses or similar means. Rose bushes are very susceptible to fungal diseases, such as black spot and powdery mildew, especially when their foliage is kept too wet.
Allow rose hips to develop by leaving dead flowers on the plant. The flowers are typically pollinated by insects, or pollinate themselves in some varieties, so there is no need to pollinate by hand unless you are breeding specific plants together. Leave the flowers on the rose plant without cutting them. After they wither, small fruits known as rose hips will develop in their place.

Water: Roses require more water than most other landscape plantings, especially during the first year as the plant is getting its roots established. The best way to water your roses is with drip irrigation. It concentrates the water at the root zone where it is needed, and keeps the foliage dry to minimize disease problems. A good, thick layer of organic mulch will help conserve moisture, reduce weeds, and encourage healthy root growth. As the mulch breaks down, it will also add organic matter to the soil.
Plant the seeds. Some store-bought seeds can be planted immediately. If you germinated your own seeds as described above, plant them as soon as they begin to sprout. Plant with the sprout pointed downward, as this is the root. Lightly cover them with soil, about 1/4 inch (6 mm) deep. Space seeds at least 2 inches (5 cm) apart to minimize competition.[5] 

I am curious... it seems that you are just supposed to "soak" the cut stems for a week or more in water.... which is mostly what people normally do with cut roses. But whenever I put roses my boyfriend brings me in water, they just fade within a week or so. I'll "feed" the roses with either sugar in the water or with the packet of plant food that comes with them. I'll cut off a small bit at an angle from the bottom of the stem evert day or so. But after a week or so they start wilting and drooping, so at that point I just take them out and hang them upside down to dry.
The next step when you grow roses from cuttings is to use a pencil or metal probe push down into the planting site soil to make a hole that is deep enough to plant the cutting up to about 50 percent of its overall length. Place the cutting that has been dipped into the rooting hormone into this hole. Lightly push the soil in around the cutting to finish the planting. Do the same thing for each cutting keeping them at least eight inches apart. Label each row of rose cuttings with the name of the mother rose bush it was taken from.
While your cuttings take root, keep them covered and moist. In a garden bed, a simple DIY mini greenhouse does the trick. Just place a bell jar, a garden cloche or an overturned mason jar over the cutting. A clear plastic bottle with the bottom cut out and the cap removed works, too. Water the soil regularly to keep it moist, but not soggy. Your mini hothouse will keep the humidity high inside.
Site: For most abundant blooms and greatest vigor, roses need to receive 6 to 8 hours of direct sunlight each day. In hot climates, they will appreciate receiving protection from the most intense afternoon sun. In cool climates, a fence or a warm south- or west-facing wall can add enough extra warmth to boost flower production and reduce winter damage.
Remove all but the top 2 leaflets on the stem, cutting just above the top set of leaves. You need to remove the excess leaves for the same reason we removed the flower in Step #2. They're taking up too much of the plant's energy. However we want the stem to continue to photosynthesize and feed itself until the new roots form, so we need to leave a couple of leaves.

The next step when you grow roses from cuttings is to use a pencil or metal probe push down into the planting site soil to make a hole that is deep enough to plant the cutting up to about 50 percent of its overall length. Place the cutting that has been dipped into the rooting hormone into this hole. Lightly push the soil in around the cutting to finish the planting. Do the same thing for each cutting keeping them at least eight inches apart. Label each row of rose cuttings with the name of the mother rose bush it was taken from.
Soaking the seeds is a crucial step if your seeds will germinate properly and stay clear of any diseases. You MUST not mix the bleach with the hydrogen peroxide as this results in a chemical reaction. 3% peroxide for 24 hours is just fine. This is also a good time to perform the water float test. Remove all seeds that float as they might not be viable.
Next fill your trays or pots with the potting soil. You can opt to use 50% sterile potting soil and 50% vermiculite, or half peat and half perlite. When the potting mix is ready in the trays or pots, this is the time to take off your seeds from the towel. Remember the seeds must not be removed from the plastic bag until they are ready to be planted. You lightly dust them before planting.

When pruning, be judicious. If you prune too hard in autumn, plants can be damaged beyond recovery. Instead, wait until spring, when plants begin to leaf out for the new season. (Roses are often not the earliest plants in the garden to respond to spring’s warming temperatures, so be patient.) Give the plant time to show its leaf buds then prune above that level.
Español: cultivar rosas usando semillas, Italiano: Coltivare le Rose Usando i Semi, Português: Cultivar Rosas a Partir da Semente, Русский: вырастить розы из семян, 中文: 用种子种玫瑰, Deutsch: Aus Samenkörnern Rosen ziehen, Français: faire pousser des roses à partir de graines, Nederlands: Rozen kweken uit zaad, Bahasa Indonesia: Menanam Bunga Mawar dari Biji, العربية: زراعة الورود من البذرة, Tiếng Việt: Trồng hoa hồng từ hạt, 日本語: バラを種から育てる, 한국어: 씨앗으로 장미 기르는 방법 
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