Container Rose Care

After planting, protect the plants by placing them on a porous weed barrier. They should not sit directly on the ground. The plants should also have good drainage. Roots will rot if they sit in water.

For maximum growth, the plants should have maximum sun exposure. However, in warmer climates, they may need some shade.

Pot-to-pot spacing is acceptable immediately after planting. However, when the first leaves are fully expanded, the roses need to be spaced with 16" between centers to assure good ventilation and light. Do not delay spacing after shoots begin to elongate.

Remember that proper watering is vital to the health of your rose plants. Right after potting, "water-in" plants. Two saturating, hand waterings are best. If using sprinklers, run them until the water flows from the pot weep holes. Watering frequency will depend on your climate and potting soil type. Make sure the pots don't dry out.

Water your roses in the mornings. If using overhead irrigation, turn it off before early afternoon. Make sure the foliage is dry two hours before sunset.

If humidity is below 30%, overhead mist plants periodically throughout the day. Overhead water frequently on hot sunny days that follow cloudy weather.

Start fertilizing your roses 2-3 weeks after planting. Depending on the fertilizer you choose, use the following guidelines:

• If using a dry complete fertilizer (20-20-20, for example), use 1 tablespoon per pot. If using drip systems and a liquid feed, use a balanced formula with nitrogen at 150 ppm.
• If fertilizing with 20-5-30 monthly, use 2 tablespoons per pot starting at five weeks.
• If using a slow-release fertilizer after potting, use a 90-day formula.

Remember that during rainy periods, fertilizer may leach out. Take EC readers every two weeks and fertilize pots with readings below 1.6.

Never apply fertilizer within 10 days of customer shipment. Prior to shipment, irrigate with water two times until the water runs freely from the bottom holes.

Although the plants are growing in a controlled environment, special considerations must be paid to heating, cooling, air circulation and humidity.

When temperatures are expected to dip below 36°F, plants should be in a heated environment. Avoid using propane heaters because they produce ethylene which can damage or kill roses.
If temperatures are expected to exceed 80°F, cooling should begin.
To prevent disease and ensure an even growing temperature, good air circulation is key.

High relative humidity may encourage disease growth. The growing area should be vented to allow for humidity management. To push moist air out of the growing structure, open the vents for a few hours at sunset while running the heating system.

Roses grown indoors should be hardened off before being sent to the end customer. Stop fertilizing the plants about 10 days prior to shipping. About a week prior to shipping, cool the growing environment down to about 45°F. Finally, the last two irrigations should be with enough clear water that it runs freely from the bottom of the container.

The primary concerns for outdoors are frost and wind.

When temperatures are forecasted to drop into the mid-20s, create a wind barrier by stacking boxes, peat bales or straw. Space the roses pot-to-pot to increase heat retention.

• Run overhead irrigation. This will form a layer of ice on the canes.
• Cover with plastic before dark. Remove the plastic during the day if the temperature rises.
• Cover with shade screen and overhead water to form an ice crust.

When temperatures are forecasted to drop into the teens and low-20s, create a wind barrier by stacking boxes, peat bales or straw. Space the roses pot-to-pot to increase heat retention.

• Overhead water to form ice.
• Cover with plastic if it is not snowing.
• If snowing, do not cover with plastic; let the snow cover.
• Cover with shade screen and overhead water to form an ice crust.

Once the frost is over, inspect all plants and remove any damaged canes, tips, stems and leaves. Spray with a pesticide to prevent botrytis.

Dry, windy conditions can dry out canes—even when the potting media is moist. Keep canes hydrated by misting, rather than spraying, the plants. Spraying the plants with large water droplets can over-saturate the potting media.

Roses grown indoors should be hardened off before being sent to the end customer. Stop fertilizing the plants about 10 days prior to shipping. The last two irrigations should be with enough clear water that it runs freely from the bottom of the container.