Garden Phlox Growing Tips

Garden phlox are mostly perennial flowering plants, belonging to the Phlox genus. These plants produce clusters of pretty, fragrant flowers in colors including white, pink, purple, and lavender, among others. Many gardeners plant phlox in their backyards because of their ability to attract large numbers of butterflies. These plants add a very attractive dimension to gardens, though they are very easy to grow.

Planting Spot

Garden phlox require rich soil that is moist and also drains excess water well. Planting in full sun is also beneficial to better growth of the plant. Garden phlox may be prone to powdery mildew if grown in a shaded, damp environment. Provide an open spot with plenty of sunlight and air to avoid this malady. If you have heavy, clay-like soil, you can improve the drainage by adding mature compost and peat moss. Amend the soil a few weeks before planting. Addition of the compost is also beneficial in improving sandy, light soil. When you are buying garden phlox, look for healthy plants that have a good root system. Avoid plants with dull foliage or discolored leaves.

When you are ready to plant the garden phlox, choose spots that are a distance of about 2 feet from other plants. The same is true if you are planting multiple garden phlox at the same time. This is necessary to ensure that the plant will have good air circulation as it grows and takes up some of the surrounding space. Dig out a hole in the planting spot, which is about twice the size of the pot or container in which you bought the garden phlox. Place the plant in the hole so that the top of the root ball is on the same level as the soil surface. Backfill the soil and firm the plant in place gently. Water thoroughly.


Mulching is essential, especially for young plants. Apply a couple of inches of mulch around the plant. Use bark or small pieces of wood as mulch. Mulching prevents the growth of invasive weeds. It also helps retain moisture in the soil for a longer period of time. Mulching helps maintain even temperatures, and protects the plant against sudden fluctuations.

Watering and Fertilization

Garden phlox requires regular watering, especially during the hot days of summer. Inadequate watering will affect flower growth. It is beneficial to apply compost to the planting spot every year, once or twice during the growing season. Apply fresh layers of mulch as required.

Pruning and Maintenance

Mature garden phlox must be divided every 3 years, to maintain vigor and healthy growth. Divide mature plants in early fall. Plant division also minimizes the chances of disease and root rot. As a plant grows, it must be pruned and deadheaded to maintain its shape. Thinning stalks can also help maintain good air flow around the plant, and minimize the chances of powdery mildew. After the first frost of the season kills the foliage, cut the plant to a few inches above the soil surface, so you know its location next year.