Choose disease-resistant varieties of hybrid tea roses that will work well in the space you have in your garden. Be sure the roses you choose will do well in your hardiness zone.
Dig a hole about 18 inches wide, making sure the soil is loose and fertile. If it is not, add some good quality topsoil with organic material in it to the hole and mix well with the existing soil before re-digging the hole.
Check the roots of your rose. If your rose comes in a root ball with soil, uncover the root ball, gently uncoil the roots, and place it in the ground. If it comes as a bare-root rose, Improve Your Soil suggests you make a little mound of dirt, and drape the roots over it to encourage the roots to spread out.
Locate the bud union on the rose. The bud union is where the new plant was grafted onto the old plant. The bud will be a swollen area from which the canes or stems grow. Be sure that you bury the bud union 2 inches below ground level if you are in a cold climate. In warmer areas, the bud union should be 1 to 2 inches above the ground. Lay a yardstick across the hole up against the rose to see how far above or below the surface the bud union will be when the hole is filled in. If it looks like it will be too deep or too far above the soil, adjust the depth of the hole accordingly.
Begin filling in the hole. Fill the hole halfway with dirt and then gently wiggle the rose a bit to allow the dirt to settle. Water the soil and allow it to settle again. This will eliminate any air pockets that may have formed during planting.
Fill the hole the rest of the way, and water again, again letting the soil settle. If there is a slight depression you can add a bit more soil until the ground is even.
Mulch around your hybrid tea rose with a good quality, compost mulch. Never use wood, bark or rubber mulch around your roses. Clean out and replace old mulch before each new growing season. Leftover mulch can be a breeding ground for fungus, and hybrids are especially prone to picking up diseases.
Water your roses every day, especially during hot, dry weather or if the soil appears to be parched. You can use a soaker hose to do this if you wish. Hybrid are delicate and you need to be careful to be sure they get enough water, but not too much. If the leaves begin to turn yellow and fall off, however, you may be over-watering them. Once every week you should give your garden a deep soak. Be sure to always water from the bottom and avoid getting the foliage wet so that it will not encourage fungal growth.
Weed carefully around your roses, being sure to prevent any weeds from touching the rootstock. Always keep this area weed-free. Hybrid tea roses require a lot of room of their own and weeds will compete for resources, preventing the roses from being able to reach their full growth potential.
Fertilize your rose every other week using a well-balanced fertilizer for roses. Hybrid tea roses benefit from a slightly acid soil, so use a fertilizer with a pH balance between 6.0 and 6.5. Stop fertilizing about six weeks before the first frost so that the rose will prepare itself for the winter months.
Prune your hybrid tea roses throughout the growing season to remove any diseased or damaged foliage, to train them, and to be sure they have enough room to grow properly. According to PlantAmnesty, you should prune again at the beginning of the growing season just as new growth is emerging. Make sure to remove any damaged, dead or diseased canes. After pruning, remove all cuttings and fallen leaves from the garden, bagging and/or burning it to prevent any spread of disease.
Winterize your hybrid tea rose by deadheading any rose hips, tying the canes together for support, and mounding soil and organic mulch or compost high around the bottom of the rose to protect the bud union from the cold.