Grow and Care for Obedient Plant

Grow obedient plant in moist sun with a footprint plan. Tags may also say Physostegia, or false dragonhead. It is not turtlehead.

Give it moist sun, and plan for rhizomes

Obedient plant is a native mint. Give it sun and even moisture and it holds 3 to 4 feet of late-summer spikes. [1] In rich, damp ground the rhizomes travel and form a colony. [2] A rain-garden margin or a meadow edge is a better home than a dry sage border. Stolons are shallow, so extra shoots pull easily while they are still soft. [3]

Pair it with other moist-sun meadow plants

Partners should want the same sun and even moisture: coneflower, late grasses, and other late-summer natives you can still reach to pull extra shoots. Leave a path so the colony does not erase the neighbours in two seasons.

Plant at pot depth after frost

Plant nursery starts after frost in spring, or in early fall with enough weeks for roots to take. Set the crown at the same depth it grew in the pot. Site it at the back of the border, or install edging before you plant. [4]

1. Pick full sun to light shade and ground that stays moist.
2. If the bed is small, sink a rigid collar or other edging before you plant, so rhizomes cannot run under the path.
3. Dig a hole as deep as the pot and a little wider. Do not bury the crown in a compost collar.
4. Set the plant at pot depth, backfill with the soil you dug, and water to settle.
5. Mulch the root zone and keep mulch off the stems.
6. Water through the first summer so the clump takes before it starts to roam.

Grow it in a pot if you cannot give it a barrier

A deep pot with drainage holes holds the spikes without handing the border to rhizomes. Keep the mix evenly moist. Empty the saucer after rain. Ground is easier if you have a meadow or a rain-garden edge that can take the roam.

Divide the clump every year or two

Division in spring or fall keeps the stand in bounds. Roots are shallow, so unwanted shoots also pull by hand.

1. Dig the clump when the soil is workable and not waterlogged.
2. Split it into pieces that each have shoots and roots. Discard a tired woody center.
3. Replant at the same depth, water in, and keep evenly moist until new growth takes.
4. Through the season, pull extra shoots that appear past the edge you want.

Cut dead stems in spring, and stake if it flops

Tops die back in winter. Leave the old stems until early spring, then cut them to the ground. Tall stems flop in shade, rich soil, or heat — stake early, or pinch in early summer for a shorter plant.

1. In early spring, cut last year's dead stems to the ground before new shoots tangle in them.
2. If last year's stems flopped, set a ring or stakes while new growth is still short.
3. On a windy, very rich site, pinch stems back a few inches in early summer so they branch and stay shorter.
4. Deadhead spent spike tips if you want a tidier plant and fewer seedlings. Leave seed heads if you want volunteers.

Not turtlehead — and not bee balm

Turtlehead is Chelone, a different wet-site perennial with a closed, turtle-mouth flower. Obedient plant is Physostegia, a mint with square stems and flowers you can bend on the spike. Do not copy turtlehead care onto this plant.

Bee balm is Monarda, another mint with mildew-prone whorled heads. Obedient plant is not bee balm. Read the Latin on the tag before you copy either recipe.

White spikes, pink spikes, or the species face

Culture is the same. Flower color is the choice. Do not treat a shop list of twenty names as a different plant.

P. virginiana is the straight native — pink to lavender tubes on a roaming clump. ‘Alba’ and ‘Crown of Snow’ are white spikes on the same moist-sun contract. ‘Rosea’ and ‘Vivid’ are warmer pink to magenta; they still roam.

Set it in moist sun, plant after frost, divide or pull extra shoots every year or two, stake if it flops, and read the tag so you did not buy turtlehead.