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When To Cut Back Black Eyed Susans?

Having Black-eyed Susans in the garden is a delight, especially when they bloom in summer. However, just like other flowering plants, you need to implement routines so they can develop more and bloom longer--and that means knowing when to cut them back.

So, when should you cut back Black-eyed Susans? Luckily, we have the answer below!

You should start deadheading wilted Black-eyed Susans starting from the stem so other blooming and mature flowers can get the nutrients necessary for a more extended bloom period.

Early during the summer, cut back the stems by a third so you won't run out of blooms when the others start fading.

Black-eyed Susans offer visual appeal in our gardens, and they improve its ecosystem. However, you need to know how to take care of them so they won't die off, especially under unpredictable weather. Keep reading below to learn more about growing and caring for your Black-Eyed Susans!

What Are Black-Eyed Susans? What Do They Look Like?

Black eyed Susan close up

Black-Eyed Susans acquired their name because of their dark brown pistil, which is a stark contrast against its bright and vibrant petals. Their shape resembles a daisy, but they are different flowers altogether.

They bloom and grow during the summer (June to August), and ideally, they are planted in clusters so your garden will look covered in these vibrant flowers.

These flowers are native to North America and an excellent alternative if you want to plant something other than daisies.

Besides their visual appeal, they also benefit your garden's ecosystem since they attract pollinators.

They can grow three feet tall, so you must prune them to maintain their bushy and clustered look.

Why Should You Prune And Cut Back Black-Eyed Susans?

Black Eyed Susan

It's important to prune and cut back your flowers so you can guide their growth. If you don't prune your flowers, they may become leggy or have less vibrant and smaller blooms.

Pruning and cutting back will allow you to easily spot and eliminate diseased parts so they won't spread to the rest of the plant.

The best time to prune Black-Eyed Susans would be after the flowering season when you could cut them up to 2 inches above the soil. However, you could always deadhead when the flowers fade and wilt.

In winter, you can cut the entire plant, but be careful not to cut beyond the soil line. The seedheads should remain as they can serve as food for pollinators.

After pruning, clean remnants of the cuttings to prevent pests from housing on them.

You should still protect the pruned black-eyed Susans from getting infested in the winter by covering them with mulch. This will also protect the plant from frost.

Doing this will ensure that your flowers stay healthy and receive the appropriate amount of nutrients necessary to continue thriving.

When Should I Plant Black-Eyed Susans?

Black eyed Susan vine flower growing in a peat pod.

You should plant black-eyed Susans once the weather unpredictability has passed. Ideally, you should plant them in the spring so they can develop and bloom next summer.

However, they can also be planted in the fall, as long as the temperature doesn't exceed 75F and doesn't fall below 70F.

Make sure you don't plant them in the middle of summer since the scorching heat may burn them in their early stages.

Avoid planting them in the winter since the frost could kill them, and they won't be mature enough to handle it.

What Are The Advantages Of Having Black-Eyed Susans?

Campfire Rudbeckia, commonly called coneflowers and black-eyed-susans, yellow-orange flowers

Black-eyed Susans match the vibrant and sunny atmosphere in the summer. However, these flowers are more than how they look.

Black-eyed Susans are deer-resistant, so you won't have to worry about wildlife munching on your flowers if you live near the woodlands.

Make sure to place them strategically, so that wildlife will detect their presence and stay away from your other plants.

Even when it's not the blooming season, these plants tend to be hardy and adaptable once established, so make sure they receive enough nutrients throughout the year.

Are There Drawbacks To Having Black-Eyed Susans?

Although Black-Eyed Susans are beautiful flowers that can be useful to the garden, it's still important to know their drawbacks and common issues so you'll learn how to address them.

Black-Eyed Susans are prone to fungal pathogens, which cause powdery mildew along the plant's surface. You'll spot powdery mildew easily when you see brown leaves with a white powdery substance on their upside.

To prevent this, you can apply fungicides on the plant so fungal bacteria won't have a chance to form. You should also sweep away dead leaves on the ground since this is most likely where the bacteria forms.

You should also watch out for white spots on the under and upper sides of the leaves, which is a sign of "rust" for these plants. Apply fungicides to treat this, and clean the surrounding area to prevent a repeat.

Black-eyed Susans also attract pests such as aphids, nematodes, and slugs.

You can prevent nematodes by planting Marigolds along with Black-eyed Susans. Plant prickly barriers around your flowers to repel slugs and snails from eating your leaves.

What Are The Best Black-Eyed Susan Varieties?

detailed close up of Black eyed Suzanne (Black eyed Susan, Rudbeckia herisse, Rudbeckia Hirta)

There are wide varieties of Black-Eyed Susans, each with distinct characteristics that may fit your routine best. These varieties can be divided into annual, biennial, or perennial.

Most gardeners prefer perennial plants because they grow back every year.

Check the label on your seed or pot if you want to plant only either of the three. If it is R. fulgida, the plant is a perennial. R. hirta varieties tend to only fall under biennial or annual.

Here are other varieties of Black-eyed Susans that you may spot at gardening stores:

raccoon sips water from a sandstone bird bath. birdbath is surrounded by black eyed susans. raccoon's eyes focus back at photogragher as water drips from its mouth, When To Cut Back Black Eyed Susans?

  • Prairie Sun - blooms bright orange flowers
  • Sonora - has golden petals and brown centers, resembling sunflowers
  • Toto Gold - is a dwarf variety and ideal for hedges

What Soil Is Best For Black-Eyed Susans?

Black-eyed Susans thrive in any soil type except for overly water-saturated soils. Of course, well-draining soil is still best.

If your soil dries out quickly, you can layer it with compost and mulch. Make sure the ground has a pH level ranging from 6.8-7.7.

You can check your soil's pH level by doing the following:

  • Prepare a measuring cup, spoon, containers, and a trowel.
  • Scoop soil samples from the top surface. Make sure the soil is free of external debris.
  • Mix one soil sample with 1/2 cup water and 1/2 cup white vinegar. If you see bubbles, it has an alkaline pH.
  • If you want to see if the soil is acidic, mix the soil with 1/2 cup of water and 1/2 cup of baking soda. If it fizzles, the ground is acidic.

You can also use a pH test strip, a more convenient way to test the soil's pH level.

Check out these litmus strips on Amazon.

Check out this YouTube video below to see the process:

https://www.youtube.com/watch?time_continue=83&v=xIz2YPBXuZU&feature=emb_title

How Often Should You Water Black-Eyed Susans?

Watering these flowers once a week is enough to keep the moisture level adequate. Make sure that you water only the soil. Avoid wetting the leaves, as this can cause the growth of mold and mildew.

Conversely, avoid drying out the soil, which may cause the plant to wilt and die. Also, make sure that there's enough space for proper aeration.

Which USDA Zones Are Best For Black-Eyed Susans?

Black-eyed Susans are generally hardy but thrive best in USDA zones 3-9. They thrive best under full sunlight when they're still developing (as long as it's not planted in the middle of summer).

They also tolerate partial shade but need at least 6 hours of full sun to bloom properly. Otherwise, they will naturally reach out to the sun's direction, causing awkward shapes and leggy stems.

Can You Stake Black-Eyed Susans?

You can stake black-eyed Susans, although it's not always necessary. Staking is only needed if the flowers grow taller than 2 feet.

However, this doesn't always happen, mainly if the plant is situated in a good location and provides the best conditions.

Can You Propagate Black-Eyed Susans?

Propagating Black-Eyed Susans is easy, and you can have more flowers at the end of each year if you divide them. Here's how to propagate these plants:

  • Plant them in a flowerbed.
  • Dig up clumps of them that have started to leaf out.
  • Divide them and place them in separate pots.

Make sure the ones you pot are just as small as your little finger. That way, they can grow properly.

To Finish

Black-eyed Susans are beautiful flowers that can liven up your outdoor space. They are relatively low-maintenance, so they're an excellent place to start if you're looking into planting flowers.

As always, take care of them throughout the year so they can give out vibrant blooms each season.

Made it to the end? Check out these helpful related articles below!

Does Black Eyed Susan Spread? [And How To Prevent This]

15 Best Fertilizers For Black-Eyed Susans [When And How To Apply]

How And When To Transplant Black-Eyed Susans