Asters do well when grown in pots or containers, provided a few cultural requirements are met. Choose a pot or container that is slightly larger than the original pot, but avoid using an overly large container where excess soil may hold too much moisture and rot the plant’s roots. The pot or container should be placed in an area with full sun for the best growth and optimum flowering.
Best Soil For Growing Asters in Pots
Asters are best planted in pots in early to late spring using standard commercial potting soil that is friable and drains quickly. The pot or container should have at least one drainage hole, but several holes are preferable for ample drainage as aster roots do not like being soggy. Avoid using lightweight plastic containers as the plant may topple over in high winds. A terracotta pot may be used, but keep in mind that it may dry out quickly in the heat of the summer. Ceramic, concrete, or fiberglass would all be good materials for potting your aster plants.
Caring For and Watering Asters in Planters
With minimal care, asters grow easily in pots or containers. Placing the pot in full sun but out of direct wind would be helpful to minimize water evaporation from the leaves in hot weather. Water the plants well, being careful not to overwater or make the soil soggy, and provide them with good drainage. A good rule of thumb is to water potted plants until the excess runs out of the base of the pot. Generally, watering every two to three days in average weather is sufficient, but that can also depend on the container size. In periods of extended heat, the plant may require more water at a higher frequency.
Fertilizing Asters in Pots
Fertilizing asters that are grown in pots or containers is unnecessary and may do more harm than good. Any commercial potting mix should contain enough beneficial nutrients to help the plant grow throughout the season. Too much fertilizer may promote foliage growth at the expense of flowers or even kill the plant.
Winter Care For Asters in Pots
At the lower end of their growing range, asters that are grown in pots or containers and are unprotected from winter weather may not survive. The pot or container would need to be brought indoors to a cool, but not freezing location for the winter and placed back outdoors in spring. Alternatively, the plant could be removed from the container and planted in the garden bed for winter and replanted in the pot or container in spring. In either case the plant should be cut back to just a few inches above the soil line and stored for winter.
Growing Asters Indoors
Asters would not do well growing indoors as they require exposure to cold temperatures for their dormancy period. They would not make a good houseplant.