Past Articles Library | How to Plant and Grow Kniphofia
Kniphofia or Red Hot Poker is a unique perennial plant that starts out looking like grass. As the growing season continues, the “grass” sends up a flower stalk that is covered half way up with downward facing, tubular blooms. Depending on the variety, these blooms can be red, orange, yellow or green.
When it comes to growing this perennial flower, you will need to consider a few things. First, Kniphofia is only hardy in USDA Plant Hardiness Zones 5 through 10. Beyond this, you will need to have a sunny location that contains moist but well draining soil. Finally, you will need space. The mature size of this plant is 36 to 40 inches, which is not the gardening challenge. What is the challenge is the spacing. Red Hot Poker requires 18 to 24 inches between each plant.
Now that you have decided to grow Kniphofia and have found the perfect location, the next step is to learn about their propagation techniques. This perennial can be propagated by either seed or rhizomes. If you decide to grow Red Hot Poker from seed, make sure to purchase it verses getting some from a gardening friend. Collected seeds from your friend will typically not grow “true.”
Seeds of the Kniphofia can be stared indoors or directly planted outside after your local frost free date but regardless of when you decide to plant, the seed needs a special treatment. What is this treatment? The seed of the Red Hot Poker needs to be exposed to the cold. This treatment is easily achieved by first moistening a paper towel and then wringing it out to remove extra water. Next, sprinkle the seeds onto the moistened paper towel. Roll the paper towel up so that you encase the seeds in the paper towel. Place the towel in a zip up like plastic bag, push out the extra air, seal, and put the bag in the refrigerator. Keep the seeds in the fridge for at least four weeks.
If you decide to start your seeds indoors, the first step is to pull out your calendar. You will need to plant your Kniphofia seeds six to eight weeks prior to your local frost free date. Once you have that date, you can plan your planting schedule.
Unlike other plants, the Red Hot Poker does not do well if the taproot is disturbed by transplanting. To prevent this, the best approach is to simply plant your seed in a peat pot. Once you are ready to plant, arrange your peat pots on a tray and fill with a well draining potting soil. Lay three seeds on the soil surface, and barely sprinkle a little peat moss on top. While the seeds of this plant are small and would normally not need to be covered, the slight covering of peat moss keeps the seeds moist.
Once all the seeds are planted, mist the soil surface. Place your planted peat pots on a sunny windowsill. Keep the soil moist by misting on the top and watering from the bottom by placing the peat pots in a container of water. After the peat pots have darkened, remove from the water and place on the sunny windowsill. The darkening of the pots is an indication that the soil is moist.
Seed germination will take between 21 and 28 days. Once the seedlings have appeared, remove the weakest seedlings from each pot so that only one remains. Continue to take care of the seedlings until they reach two inches in height and your local frost free date has passed. At this point, you can plant your Kniphofia in the flower garden after the seedlings have been hardened off.
When planting your peat pots in the garden, there is a simple technique to follow to avoid moisture wicking. What is moisture wicking? Well, when it comes to peat pots, if the lip of the peat pot is allowed to stick above the soil level then the moisture will be wicked away from the pot. To prevent this, one needs to make sure that that lip is covered with soil or torn away. It is also a good idea to simply tear some of the sides of a peat pot to make sure that it does not constrict the roots. Doing this latter technique will not disturb the taproot.
If you want to directly seed into the garden space, this will need to be done after your local frost free date. While you are waiting for that date to arrive, you can begin to prepare the garden space. This really has nothing to do with removing weeds; instead it has to do with preparing the soil for this perennial. To improve the drainage of the soil, mix in a good amount of well seasoned compost before planting the seed.
When you are ready to plant outside, take your ruler and mark off every 18 to 24 inches with powdered milk. This is the spacing by which you need to plant your seed(s) and/or plants. Next, sprinkle three seeds on each marked spot. Once all the seeds have been planted, mist until the soil is evenly moist. Keep the soil moist and in about a month you will see your seedlings emerge. As soon as you can, thin the seedlings out so that only one exist per 18 to 24 inches.
Another choice of propagation is through rhizomes. These rhizomes need to be planted two to three inches deep and 12 to 24 inches apart in the spring or summer.
Regardless of which propagation technique you choose, you will need to add straw or leaf mulch to the plants prior to their first winter. Once the flowers are spent, cut the flower stalk down to the leaves. When it comes to sharing your plant wealth, you can easily divide them but this should only be done every five years or more.
While most gardeners grow this perennial plant for its blooms, which appear from summer to fall, there are other aspects of this plant that makes it a landscape favorite. One is the texture that the “grass like” leaves provide in the landscape. The second reason this plant is a great one for any landscape design is the fact that it attracts many different type of nectar loving animals, which includes hummingbirds, and orioles.