Did you planted your pennyroyal somewhere where it can get at least 4 to 6 hours of sunlight daily?
Did you planted your pennyroyal in rich soil, amended with organic matter?
Do you water your pennyroyal regularly?
Do you fertilize your pennyroyal?
Do you keep your pennyroyal from the uncontrollable spread by cutting it?
Are you making sure that the plant doesn't escape through the drainage hole into the landscape if you are growing it in the container?
Do you keep your pennyroyal free of pests and diseases?
Pennyroyal plants grow best in partial sunlight, but full sun is also tolerated as long as there is adequate moisture.
Pennyroyal plants grow at their best in moist, rich soil amended with organic matter. These plants also grow in clay or sandy conditions, and sometimes less than ideal soil can help to check the plants' rapid growth.
Regular moisture is important to a thriving pennyroyal plant. The surface of the soil should feel moist to the touch. Pennyroyal grows well in damp areas like stream banks or low-lying depressions in the landscape.
Chemical fertilizers aren't necessary to grow healthy pennyroyal plants. The plants can get all the nutrition they need from soil rich in organic humus from leaf mold, manure, or compost. Too much fertilizer will reduce flowering in pennyroyal plants.
Cutting back your pennyroyal plants is an important part of keeping it in bounds. Pennyroyal spreads indefinitely by creeping stolons, in the same way, mint does and can become invasive if not kept in check. Pull up the edges of your pennyroyal plant where it is rooting and spreading, and trim as desired to keep the plant in its designated spot.
Pennyroyal will grow in pots of any size and tolerate being root-bound. Take care that the plant doesn't escape through the drainage hole and into the landscape if you're trying to keep it contained.
God job! You are taking good care of your pennyroyal plant.
As a natural pest repelling plant, pennyroyal is troubled by few insects. However, powdery mildew and mint rust can trouble plants growing in crowded, damp, shady conditions. Keep your pennyroyal plants disease-free with adequate sun and spacing, and with well-draining soil.
https://www.thespruce.com/pennyroyal-plant-care-and-growing-guide-4688581
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Sreten null
Hi! I’m Sreten Filipović. I graduated from the Faculty of Agriculture at the University of Belgrade, with a master's degree in Environmental Protection in Agricultural Systems. I’ve worked as a researcher at Finland's Natural Resources Institute (LUKE) on a project aimed at adapting south-western Finland to drought episodes. I founded a consulting agency in the field of environment and agriculture to help farmers who want to implement the principles of sustainability on their farms. I’m also a founding member of the nonprofit organization Ecogenesis from Belgrade whose main goal is non-formal education on the environment and ecology. In my spare time, I like to write blog posts about sustainability, the environment, animal farming, horticulture, and plant protection. I’ve also published several science-fiction short stories.
You can find me on LinkedIn at https://www.linkedin.com/in/sreten-filipovi%C4%87-515aa5158/