While there are many selections of hyssops available, there are two distinct types: ones with large flowers like 'Desert Sunrise' (figure F) and small-flowered ones like Agastache neomexicana (figure G). The large-flowered hyssops are a hummingbird favorite while the smaller-flowered cultivars are a favorite of butterflies. Another great hyssop quality? They repel deer.Planting and Maintenance of Hyssops
To plant his hyssops, Salman begins with a bed of loose soil. Using a hand trowel, he makes individual planting holes in between his drip irrigation system. To enrich the soil, he adds a generous handful of organic fertilizer. Be careful not to overdo it because hyssops don't like soil that's too rich. Next he adds a handful of high-quality organic compost to serve as the backfill behind the plant's root ball.
Before putting the hyssop in the ground, scoring the sides of the root ball will help the roots spread once in the soil. Plant it so the top of the root ball is just below the level of the soil. Creating a depression in the soil around the plant will help to hold any extra irrigation water.
Although they're low maintenance, hyssops like an annual application of mulch and fertilizer in the fall. Salman recommends leaving plant stems standing over the winter to help them through the cold season, then cutting the plant back in mid-spring.
Because the plants grow up, rather than out, they may need to be staked during the summer. "Some of the larger selections like 'Desert Sunrise' may need occasional staking if they get floppy, but it only needs to be done once," says Salman.
Agastaches like to have their crown (the area between the roots and the stems) protected from excess winter moisture. Gravel mulch will pull double duty for the plants. It will help keep the roots cool in the summer and protect them from freezing temperatures in the winter.