Black-Eyed Susan in Zone 6B — Midwest

Black-Eyed Susans are a Midwest garden staple for good reason. Their cheerful yellow petals bring sunshine to your yard all summer long, and they’re fantastic for attracting pollinators. Plus, they make excellent cut flowers to bring a bit of the garden indoors.

Our Midwest weather can be unpredictable, but Black-Eyed Susans are tough. With a 183-day growing season, you've got plenty of time to get them established and enjoy their blooms. Just keep an eye on the weather, and you'll be rewarded with a beautiful display.

Starting Black-Eyed Susans indoors isn't essential, but it can give you a head start, especially if you're impatient for those first blooms. If you want to try it, sow seeds indoors from early to late February, about 8 weeks before you plan to transplant them outside.

Use seed trays filled with a good seed-starting mix. Keep them warm (around 70°F) and provide plenty of light with a grow light. Bottom watering helps prevent damping off, which can be a problem in our sometimes-humid springs.

Transplanting Black-Eyed Susans outdoors is best done in early April through early May. Before you plant, harden off your seedlings by gradually exposing them to outdoor conditions for about a week.

Space them 12-18 inches apart in a sunny spot with fertile soil. Keep an eye on the weather forecast – we can still get a late frost in early spring, so be ready to cover them if needed. Remember, Black-Eyed Susans are perennials, so consider buying established starts if you want flowers the first year.

Direct sowing Black-Eyed Susan seeds is a simple and effective method. Wait until mid April through mid July, when the soil has warmed up a bit.

Prepare the soil by loosening it and removing any weeds. Sow the seeds about ¼ inch deep and keep the soil consistently moist until they germinate. Thin the seedlings to 12-18 inches apart once they are a few inches tall.

Black-Eyed Susans are pretty low-maintenance when it comes to watering, especially once they're established. Remember they're native prairie flowers, so they're built to handle drier conditions.

During the first few weeks after planting, water regularly to help them get established. After that, let the soil dry out a bit between waterings. Stick your finger about 2 inches deep into the soil – if it feels dry, it's time to water. Usually, about an inch of water per week is plenty, but you might need to water more during summer heat spells.

Water at the base of the plants to avoid getting the foliage wet, which can encourage fungal diseases in our moderate-to-humid climate. Yellowing leaves can indicate overwatering, while drooping leaves can signal underwatering. A layer of mulch around the base of the plants will help retain moisture and keep the soil cool.

Deadheading Black-Eyed Susans will encourage them to produce more blooms throughout the season. Simply snip off the spent flowers just below the flower head.

If you want to leave some seed heads for the birds or to encourage self-seeding, that's fine too. In late winter or early spring, before new growth emerges, cut back the entire plant to a few inches above the ground.

Black-Eyed Susans will start blooming in late June and continue through late October. You'll know they're ready to harvest when the flowers are fully open and the petals are bright and vibrant.

Cut the stems at an angle, leaving as much foliage on the plant as possible to encourage continued production. Deadheading spent blooms will also keep them coming. As the first frost approaches in mid- October, you can still harvest any remaining blooms, but the plant will naturally start to slow down.

Here are some common problems you might encounter with Black-Eyed Susans in the Midwest:

Powdery Mildew

• What it looks like: White or grayish powdery coating on leaves, stems. Leaves curl, yellow, and die.
• What causes it: Fungi thrive in warm days, cool nights, and moderate humidity. Dry leaf surfaces actually favor it.
• How to fix/prevent it: Improve air circulation through spacing and pruning. Remove affected leaves. Neem oil or potassium bicarbonate sprays help. Milk spray (1 part milk to 9 parts water) is surprisingly effective. Plant resistant varieties.

Septoria Leaf Spot

• What it looks like: Small, circular spots on leaves that start as dark brown or black and eventually develop gray centers.
• What causes it: A fungal disease that spreads quickly in wet, humid conditions, which we often get during our wet summers.
• How to fix/prevent it: Remove and destroy infected leaves. Improve air circulation. Apply a fungicide if the problem is severe. Water at the base of the plants to avoid wetting the foliage.

Aphids

• What it looks like: Clusters of tiny soft-bodied insects (green, black, or white) on stems and leaf undersides. Sticky honeydew residue. Curled or distorted new growth.
• What causes it: Rapid-reproducing sap-sucking insects. Populations explode in warm weather. Ant colonies may farm them for honeydew.
• How to fix/prevent it: Strong water spray knocks them off. Encourage ladybugs and lacewings (natural predators). Insecticidal soap for heavy infestations. Neem oil works systemically. Avoid excess nitrogen fertilizer (it attracts them).

Midwest Specific Challenges: The moderate-to-hot heat, moderate-to-humid humidity, and wet-summer rainfall in the Midwest can create ideal conditions for fungal diseases like powdery mildew and septoria leaf spot. Good air circulation and proper watering practices are key to preventing these problems.

Black-Eyed Susans make great companions for a variety of plants in the Midwest garden. They pair well with tomatoes because they attract pollinators that help with fruit set.

Squash also benefits from the presence of Black-Eyed Susans, as the pollinators they attract can help with squash production. Herbs like basil and oregano are good companions because they can help repel some pests that might bother Black-Eyed Susans. Avoid planting them near anything that prefers very dry soil, as Black-Eyed Susans need consistent moisture, especially when getting established.