Rudbeckia is a genus of flowering plants in the daisy family, Asteraceae. They are native to North America and are commonly known as black-eyed Susan, coneflower, and brown-eyed Susan. Rudbeckia plants have daisy-like flowers with a prominent central cone. The flowers come in a variety of colors, including yellow, red, orange, and brown. The foliage is usually green and coarsely toothed. Rudbeckia plants are easy to grow and can tolerate a wide range of soil and light conditions. They are drought tolerant and attract birds, butterflies, and other pollinators.
Planning Your Garden With Rudbeckia
As you plan your garden, it's important to think about the spacing, size, light, and nutrient requirements of all of your plant and how they'll grow together.
Some plants require more water than others, while other plants require dry soil. At the same time, some plants prefer full sun, and other plants need the shade to survive.
By studying what each plant requires and planning ahead where all of your plants will grow best, you can optimize your garden space.
| Life Cycle | Rudbeckia is a perennial. |
| USDA Zone | The USDA Hardiness Zone range for Rudbeckia is 3 to 9. |
| Cold Tolerance | Rudbeckia is generally hardy in USDA zones 3 to 9, which means it can tolerate temperatures as low as 25. |
| Days to harvest | The minimum number of days to harvest rudbeckia is 60-90 days. |
| Average size | The average size of a full grown rudbeckia plant is between 2 and 4 feet tall and 1 to 3 feet wide. |
| Spacing requirements | Rudbeckia is best grown in full sun and in well-drained soil. They should be spaced 12-18 inches apart in the garden. |
| Sun tolerance | Rudbeckia is a sun-loving plant and will thrive in full sun to partial shade. It can tolerate temperatures up to 95°F (35°C). |
| Shade tolerance | Rudbeckia is a relatively shade-tolerant plant, but it does best in full sun. It can tolerate partial shade, but it will produce fewer flowers and may become leggy and weak. |
| Water requirements | Rudbeckia plants prefer moist, well-drained soil. They should be watered regularly to keep the soil evenly moist, but not saturated. During the summer months, they may need to be watered every 3-4 days, depending on the weather. In the winter, they should be watered less frequently, usually only when the top inch of soil is dry. |
| Fertilizer | The amount of fertilizer you should use when growing rudbeckia depends on the type of fertilizer you are using and the soil conditions. Generally, a balanced fertilizer with an NPK ratio of 10-10-10 or 20-20-20 is recommended. Apply the fertilizer at a rate of 1 to 2 pounds per 100 square feet of garden area. |
| Soil pH | The optimum pH for growing Rudbeckia is 6.0 to 7.0. |
Why Rudbeckia is Popular
People like to grow rudbeckia for its bright, cheerful flowers and its hardiness. Rudbeckia is a low-maintenance plant that is easy to grow and can tolerate a variety of soil and light conditions. It blooms from late summer to early fall and provides a long-lasting show of color in the garden.
Companion Plants For Rudbeckia
Companion planting is a great way to maximize your garden space and get the most out of your plants. By planting certain plants together, you can help each other thrive. In some cases, you can even help each other repel pests.
Popular companion plants for rudbeckia include:
Common Pests For Rudbeckia
Plant pests are a common problem for gardeners. By understanding what pests are common for your plants, you can take steps to prevent them from damaging your plants.
When you grow rudbeckia, keep an eye out for these common pests:
- leaf miners
- slugs
- aphids
- caterpillars
- spider mites
USDA Zones
USDA zones are a popular way of determining which plants can grow in your area. Zones tell you when your average first and last frost date are, as well as how cold you can expect it to get in the winter.
Our site works best if you choose your zone from the list below. If you do not know your USDA zone, then you can use our zone map.
