Does your garden look a bit gloomy? If it is, you need to think about growing black-eyed Susan plants in the garden. The yellow flowers of these plants will create a cheerful garden. They look beautiful and quite enchanting when the flowers cover a large area. Moreover, one of the best things about the plants is that they are pretty easy to grow.
What is Black-Eyed Susan?
Sunny, happy, and carefree are some of the attributes that you will see in black-eyed Susan flowers. The plants that bear these flowers are scientifically named Rudbeckia hirta. Some people also call them brown-eyed daisy or gloriosa daisy. They are indigenous of North America and grow mostly in USDA zones 3 to 9.
These are some fact about this plant:
1. It is a wildflower
Many gardeners usually consider Rudbeckia as wildflowers since they are native to their area. In addition, they can be quite aggressive. If you do not take care of them properly, they may invade your garden and cause other plants to suffer from lack of nutrition.
2. Annual, Biennial, and Perennial Plants
Some of the Rudbeckia cultivars are annual plants. However, you can also find biennial or perennial Rudbeckia. In consequence, you can find ones that suit your gardening style.
If you don’t want to sow Rudbeckia seeds every year, you can choose the perennial variety. However, if you love to have different flowers each year in your garden, then you must choose the annual ones.
This flowering plant is mostly propagated from seeds. However, you can also transplant the divided plants into new plants. The seeds of Rudbeckia can take a long time to germinate. However, when they germinate successfully, the sprouts will grow into strong and easy to maintain plants.
4. Plant Description
Black-eyed Susan plants can grow up to 0.45 m wide and 0.9 m tall or even taller. Their leaves are hairy. They are medium size, between 10 cm and 18 cm long. The plants bloom between late summer and early fall. The blooms are daisy-like with bright petals and dark brown center. At a glance, they look like the miniature of sunflowers.
The Rudbeckia flowers are about 7 to 10 cm wide. Most of these flowers are yellow. However, certain cultivars will give you orange, golden, and red flowers. It doesn’t take long for you to enjoy this beauty since Rudbeckia will bloom in the first year.
Growing Condition for Black-Eyed Susan
Rudbeckia plants are easy to grow. However, they will not grow well if you do not plant them in the right environment.
These flowering plants are well adapted to various types of soil. You can grow them in sandy, loamy, or clay soil. However, they will have growing difficulty if the soil is poor. Therefore, you need to make sure that the soil in your garden is rich in organic material. In addition, the soil must be well drained and neutral (pH level of 7).
Black-eyed Susan plants tend to love warm temperature. The seeds germinate best in temperature of 21oC. At this temperature, they will sprout roots in 1 to 2 weeks. However, in lower soil temperature, it can take up to 30 days for them to germinate. Therefore, it is better to start the seeds in between March and May.
The best place to grow Rudbeckia is at a sunny spot. Getting 6 hours of sun is important for the plants to grow. Sun will also speed up the germination process. These flowering plants can adapt to partial sun. However, they may bloom less in this kind of environment.
Some of these flowering plants do not tolerate drought very well. They require moist soil to thrive. However, you need to make sure that it is not too wet. Black-eyed Susan that grows in damp environment will have higher risk of suffering from plant diseases or affected by pests.
There are various cultivars of Rudbeckia that you can choose:
This dwarf type of black-eyed Susan is perfect for you who have limited space in the garden. Rudbeckia hirta sonora is only 30 cm tall. Most importantly, it has stunning flowers. The center is dark and the petals are yellow with reddish brown inner ring. This short-lived perennial will come back each year with those wonderful flowers.
Sonora grows best in USDA hardiness zones 4 to 9. Moreover, it is drought tolerant. Therefore, it is okay to have dry soil in between watering. Sonora needs full sun to thrive. In winter, its roots need some protection from the cold temperature. The best way to protect them is mulching the soil in the fall.
2. Irish eyes
This cultivar grows up to 0.75 m tall and offers you with attractive flowers. They have yellow petals and green eye. That’s why it is called Irish eyes. This perennial Rudbeckia can survive the winter in USDA zones 4 to 9. If you want to have it in your garden, plant the flowering plant in a sunny spot and water it once a week.
3. Cherokee sunset
This annual black-eyed Susan is almost in the same size of Irish eyes. However, this plant has attractive flowers, unlike common black-eyed Susan. The flowers look like dahlia with orange and yellow petals and a dark center. You can see the plant flowering in early summer until the first frost.
Cherokee sunset must be planted in full sun. In addition, it is also drought tolerant. Though it is not perennial, you will likely watch the plant grows in your garden each year without you sowing the seeds. It is because Cherokee sunset will self-seed if you let the seeds dry on the plant.
4. Indian summer
This type of Rudbeckia is commonly used in landscaping. Its flowers bloom in the first year. They are bright yellow with dark center. You can grow Indian summer as short-lived perennial if you live in USDA zones 3 to 7. However, you can also grow it as annual.
This plant is drought tolerant, once established. It can stand heat very well too. Indian summer grows well in sunny a spot. Moreover, if you grow these flowering plants in your garden, you need to space them properly.
This compact cultivar is good for small garden. It is about 30 to 60 cm high and 30 cm wide. You can even try to grow it in a container. If you grow it in a pot, you must provide a large enough pot because the roots can grow quite long. Rudbeckia toto requires full sun, moderate watering, and moist and well-drained soil. Once established, the plant can tolerate drought very well.
Toto has golden yellow flowers with chocolate cone. They are about 8 cm in diameter. Similar to other cultivars, toto blooms between the summer and the first frost. It usually offers large number of flowers that you cannot almost see its foliage. For best result, you must grow it in hardiness zones 5 to 8.
If you want unique black-eyed Susan flowers, you must go for Rudbeckia Maya. The shape of these flowers is almost similar to mums. They have golden yellow frilly petals that are arranged in layers. The plant is quite compact since it only reaches 45 cm tall.
Another good thing about Rudbeckia Maya is that it is resistant to diseases. In addition, this plant is also tolerant to dry environment once established. This cultivar will be flowering from midsummer to fall. In the right environment, Maya will grow as biennial. However, the plant sometimes grows as annual and self-seeds easily.
7. Cherry brandy
If you want to create a more vibrant garden, you have to grow Rudbeckia cherry brandy. The flowers of this cultivar have vibrant red petals with dark cone. You will see the plant blooms numerous flowers continuously during the early summer to early fall.
Cherry brandy is tolerant to dry environment. It requires weekly watering. Moreover, this cultivar of Rudbeckia grows well in hardiness zones 4 to 7. This short-lived perennial can grow up to 60 cm tall.
How to Grow Black-Eyed Susan from Seeds
Some gardeners recommend you to grow this flowering plant directly to the ground. It is because some of the cultivars cannot grow well in containers due to their root characteristic and size. However, you can choose the dwarf varieties to grow in containers. For this kind of planting, choose a container that is wide and deep.
To grow black-eyed Susan, you need to perform these steps:
In this step, you need to prepare the planting spot. First, choose a sunny spot to grow this flowering plant. After that, you need to loosen the soil and add compost or other type of fertilizer to the soil.
If you want to grow black-eyed Susan in containers, you must first get containers, high quality potting mix, slow release fertilizer, and gravel. The containers for the Rudbeckia must have drainage holes and big enough for the plant. Add a layer of gravel at the bottom of the pots. After that, fill in the pots with the potting mix and add the slow release fertilizer into the potting mix.
2. Planting the seeds
Once the site or container is ready, you can start planting the Rudbeckia seeds. You must not plant them too deep because they require sun to germinate. Place the seeds on the surface of the soil and cover them loosely with soil. Keep the soil moist until the seeds germinate.
3. Thin the seedlings
In about a month or less, you will see the seedlings appear. Thin the seedlings when they are about 5 cm tall. Thin them so that the seedlings are 30 cm apart. When you are performing this step, you need to remove the weakest seedlings. Thinning is essential in growing Rudbeckia plants because they need excellent air circulation.
Caring for the Plants
Black-eyed Susan requires low maintenance. These are what you need to do in caring for the plant.
1. Deadheading the flowers
If you want the Rudbeckia to bloom continuously until fall, you need to deadhead the flowers once a week. When you see some of the flowers start dying off, you must cut them immediately. If your black-eyed Susan only grows one flower on one stem, you must cut the stem closer to the base. However, if there are multiple flowers on one stem, you only need to cut the flowers.
2. Weekly watering
Most Rudbeckia varieties require moderate watering. They love the soil moist but not wet. In consequence, you need to water the plant once a week. If the weather is hot and the soil is dry, you must water the soil more often. Rudbeckia that grows on a pot also need more frequent watering.
3. Removing the seed heads
This flowering plant self-seeds easily. If you want to curb their growth in the next spring, you had better remove the seed heads before they are completely dry. Therefore, there will be no seeds left in the soil. However, if you want to have them again next year, you don’t need to remove the seed heads.
4. Dividing the plants
For you who grow perennial Rudbeckia, it is essential to divide the plant in every 3 years. If you do not perform this step, the plant will have less blooms in the next years. Root division must be done in early fall or the spring.
Before you do this step, you need to prepare a new planting site before you divide the plants. After it is ready, you can dig the soil around the plants and remove them carefully. Next, you must clean the roots from the soil. Choose a plant that has at least 3 healthy shoots and grow it in the new site.
Dealing with Pests and Diseases
Rudbeckia is prone to suffer from diseases that are caused by fungi. Some of those diseases are powdery mildew and leaf spot. To prevent the fungal infection, you must apply fungicide early in the season. In addition, you must make sure that the soil is not wet and the plants have good air circulation.
Moreover, slug sometimes eat the base of Rudbeckia. They will attack this plant when the soil is wet. Therefore, you must be careful in watering the plant. Keeping the soil moist is important but you must not cause the soil to be wet.
Benefits of Growing Black-Eyed Susan
1. Attract pollinators
Rudbeckia flowers attract pollinators. When they bloom, butterflies, bees, and other pollinators will come to these flowers. Therefore, it is a great idea to plant Rudbeckia on the borders of your kitchen garden. The pollinators that come because of these flowers will help the pollination of other flowers.
2. Excellent cut flowers
The flowers of this plant are excellent cut flowers. They are beautiful and cheerful. Arranging them in a vase along with other flowers will make your interior looks more attractive. Another good thing about the flowers is that they can last up to a week in your vase.
3. Black-eyed Susan root tea
Herbalists believe that black-eyed Susan dry root tea is great to improve the immune system. Drinking the tea will help you to fight common colds. You can also use it to treat cuts, dropsy, and earache.
Black-eyed Susan may be a native wildflower. However, its beauty will lighten up your garden beautifully from summer to fall. In order to make your garden looks more attractive, you can grow a combination of several Rudbeckia varieties that have different colors of flowers.