Growing roses in containers
Now’s the time to start. Most of all, think about
container size, soil mix, how you’ll feed and water
Why bother growing roses in pots? Heavy, unworkable soil like
Claudia Brotherton has in her San Diego garden is one good reason.
Containers allow her to grow roses that she couldn’t grow
otherwise. More than 150 plants–miniatures, polyanthas, floribundas,
hybrid teas, and grandifloras –thrive in her containers; one has syayed
in the same pot for four years.
The photographs above show how Mrs. Brotherton prepares and plants
bare-root roses. If you’d like to try her method, this is the time
Choose any favorite rose, or use the list at right to start.
Smaller, more compact roses (miniatures, floribundas, polyanthas) are
usually best if you’re a beginner; they can also stay longer in
Pot size and type. Before buying a container, consider the size,
shape, and habit of the rose you intend to plant. For most of her
roses, Mrs. Brotherton uses 18- to 20-inch Mexican clay pots. A typical
5-gallon plastic container (12 inches wide by 14 inches deep) is
suitable for compact growers. Larger roses, such as tree roses, need
bigger pots for proper proportion as well as for root space.
Wood has an advantage because it doesn’t heat up on warm days.
Half-barrels (23-inch inside diameter) provide plenty of root space for
large roses, but they are heavy and awkward to move. Plastic containers
keep moisture in longest.
Soil. Unamended garden soil rarely works well for growing roses in
containers; roses prefer a faster-draining mix. You can buy packaged
soil mix ($3 to $4 a cubic foot) or make your own (equal parts fine
sand, peat moss, and fine fir bark make a good basic mix). Since the
basic ingredients have little nutrient value, you’ll need to add
fertilizer right away if you make your own mix. Most packaged mixes
include starter fertilizer.
Water. Mrs. Brotherton’s roses are all watered by an
automatic drip system. She uses spray-type emitters to wet the entire
rootball. On hot summer days, she sets her system to come on twice a
day for about 5 minutes each time; otherwise she waters needed.
How often you’ll need to water depends on the weather, the
size of the pot, the soil mix, and the size and condition of the plant.
Feel the soil; water when it’s dry to the touch 1 inch below the
Fertilizer. Watch and judge how well the rose grows. Healthy
green leaves, vigorous growth, and plenty of flowers mean fertilizer is
adequate; slow or off-color growth usually indicates not enough
Most rose growers use either a granular slow-release fertilizer
three or four times a season or a dilute liquid fertilizer with each
Repotting. Repotting is usually necessary every two to three
years, though some roses grow well much longer in their containers. Main
sign of overgrowth is a plant failing to respond to fertilizer. When
roses are dormant, knock them out of their containers; prune roots,
discard old soil, and replant.
Winter protection. In coldest climates (where temperatures dip to
20| and hold for three or more days), roses growing in containers are
susceptible to damage. If possible, move pots to a protected spot, such
as a garage or storage shed, for the coldest months. Don’t let soil
dry out; check frequently and water if necessary.
Photo: 1. Prune roots so all fit into pot without bending or
twisting. Cut away any broken portions
Photo: 2. After filling pot halfway, build and then firm a cone of
soid to fit under the pruned root system
Photo: 3. Spread roots over cone. Check final height of plant in
pot; set so bud union (swelling where rose was budded to its rootstock)
is level with pot rim
Photo: 4. Add remaining soil, firming it as you go, until pot is
filled to about 1 inch from rim
Photo: 5. Water until pot drains, then water again. Add more soil
if necessary. Make sure soil is thoroughly wetted
Photo: Roses thrive in low bowls, tapered pots, and straight-sided
pots in Claudia Brotherton’s San Diego garden. To keep roots from
anchoring in soil below, pots rest on aggregate concrete pads; lava rock
is spread between