Regular watering for best results. The Mexican heather is a densely branched sub-shrub with small, glossy leaves. Cuphea hyssopifolia varieties ranges from 1 to 3' tall with tiny lavender, purple, or white flowers. They can be trimmed to most shape you want, and grow back rapidly.
Germination takes a week and a half with irregular results.
In Phoenix, the Mexican Heather Blooms profusely the year around. The most common hybrids are 'Allyson' with purple flowers, and 'Alba' with white flowers. This site contains information and pictures for more than 2000 species of plants. The CD of the site Enjoy the much larger pictures.