Foxgloves are an old-fashioned perennial flower. The flowers grow along a tall central stem. Their spiky appearance is a good contrast to other flowers in the garden. Yellow foxgloves grow only two to three feet high, in contrast to varieties of other colors, which can grow up to six feet high.
Pick a spot in partial shade in which to grow yellow foxgloves. They do well grown in a woodland-type garden, alongside other shade-loving plants. The soil should be moist, rich and well-drained.
Improve the planting site. Add an inch of compost and an inch of peat moss to the surface of the soil in the garden bed. Dig them into the top layer of soil with a shovel, then rake the bed smooth.
Sow seeds of foxglove in spring or summer directly into the garden bed where the plants are to grow. Scatter a few seeds in clusters about 18 inches apart in all directions. Cover lightly with garden soil. If growing yellow foxgloves from small bedding transplants, plant them in small holes about 18 inches apart in all directions in the prepared bed.
Water the seed bed with a fine mist from a hose end sprayer. Check the seed bed daily and mist as needed to keep it moist. Water newly transplanted bedding plants with a hand watering can. Water every few days until they are established and begin active growth.
Thin seedlings of direct seeded foxglove to the strongest seedling in each cluster when they are about two inches high.
Insert a 24- to 36-inch bamboo stake next to the foxglove plants when they are about 4- to 6-inches high. These will support the stems when they become top-heavy with blossoms or from being blown over in high winds.
Spread organic mulch such as hay, straw or buckwheat hulls in a 2- to 7-inch layer around the yellow foxglove plants.
Cut off the faded foliage in autumn when it dries up or is killed by frost.
Cover yellow foxglove with a protective winter mulch that is 12- to 18-inches deep. Use straw, hay or evergreen boughs. Remove protective mulch in early spring but leave the regular mulch you applied in Step 7.
Remove spent flowers when they bloom the second summer after planting if you do not want them to reseed themselves in your garden.
Dig up and divide yellow foxglove every three to four years. Set the rootball on a hard surface and separate by driving the blade of a shovel through the rootball from the top down. Make such each division has both roots and stems. Replant each division to grow a new yellow foxglove plant.