Agalinis bangii prefers consistently moist soil, especially during its active growth period. Water thoroughly when the top centimeter of soil begins to dry out. Avoid overwatering, as this can lead to root rot.

Reduce watering slightly in cooler, dormant periods, but do not allow the soil to become completely dry.

Pruning is generally not required for Agalinis bangii. If the plant becomes leggy or overgrown, light trimming can be done after flowering to maintain a more compact shape.

Remove any dead or spent flower stalks to encourage further blooming or to tidy the plant's appearance before winter.

Propagation is typically achieved through seeds. Agalinis species are often hemiparasitic, meaning they benefit from growing near a host plant.

Sow seeds in early spring, either directly outdoors in well-draining soil or in pots, mimicking natural conditions with appropriate companion plants or soil treatments to aid germination.

Repotting is rarely necessary for Agalinis bangii as it is often grown as an annual or short-lived perennial.

If it is being cultivated in a pot and outgrows its container, repot in early spring before active growth begins. Use a well-draining, sandy soil mix. Handle the roots gently due to their delicate nature.