Deadheading sweet alyssum will keep the plants flowering—they will set new buds quickly. If you have a large drift of plants, shearing them by one-third would be an easier option than deadheading.

How do you keep alyssum blooming all summer?

Keep alyssum well-watered during hot, dry weather. It has few pests and diseases. In mid summer to stimulate more growth and flowering shear your alyssum plants by 1/3rd of their height. Fertilize afterward with a balanced product and water and they will regrow for a late summer flower show.

How do you Deadhead alyssum?

Shearing the plant back by about one-half its length when it starts to look played out and leggy, or when blooming slows, cleans the plant up and encourages another round of blooming. There's no need to be exact -- cutting foliage to above one of its tiny branches -- you can just grab and snip off old growth.