Chrysanthemum in Zone 6A — Great Plains

Chrysanthemums are more than just fall decorations; they're vibrant additions to your Great Plains garden, offering late-season color when everything else is fading. Their cheerful blooms brighten landscapes and make excellent cut flowers, bringing the beauty of your garden indoors. Plus, they attract beneficial insects, supporting a healthy garden ecosystem.

Growing chrysanthemums in our Zone 6A climate presents challenges. Our extreme temperature swings and variable rainfall can be tough on plants. But with careful timing, starting indoors, and attention to watering, you can successfully grow these beauties during our 188-day growing season.

Starting chrysanthemums indoors gives you a head start, especially if you want earlier blooms. Begin in mid February through early March, about eight weeks before you plan to transplant. Use seed trays with good drainage and a seed-starting mix.

Keep the soil consistently moist (bottom watering can help prevent damping off) and provide warmth and plenty of light – a grow light is ideal. Be mindful of our variable spring weather; even indoors, protect seedlings from drafts and temperature fluctuations.

Transplant your chrysanthemums outdoors mid April through mid May, once the risk of hard frost has passed. Before planting, harden off your seedlings by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the sun and wind we often experience.

Choose a sunny spot with well-drained soil and space plants 12-18 inches apart to allow for good air circulation. You can also buy potted mums in fall or starts in spring to skip the indoor seed starting.

Watering is key for chrysanthemums in our Great Plains climate, especially with our hot summers and variable rainfall. While they need consistent moisture, they don't like soggy soil. Aim for about 1 inch of water per week, but adjust based on rainfall and temperature.

The "finger test" is your friend: stick your finger about 2 inches into the soil. If it feels dry, it's time to water. Water at the base of the plant to avoid wetting the foliage, which can encourage fungal diseases in our moderate humidity.

Signs of underwatering include wilting leaves and dry soil. Overwatering can lead to yellowing leaves and root rot. A layer of mulch, like shredded bark or wood chips, can help retain moisture and regulate soil temperature.

Pruning chrysanthemums encourages bushier growth and more blooms. Start pinching growing tips every 2-3 weeks through July 4th. This forces the plant to branch out and produce more flower buds.

Simply pinch off the top set of leaves on each stem, leaving the rest of the plant intact. After July 4th, stop pinching to allow the flower buds to develop for your late-season display. As the first frost approaches around mid- October, you can cut back the plant to a few inches above the ground.

Expect your first chrysanthemum blooms late June through mid August, about 70 days after transplanting. Chrysanthemums are fall-blooming plants, so they will continue to produce flowers for weeks. Cut the flowers for bouquets when they are fully open for the longest vase life.

To harvest, use sharp scissors or pruners to cut the stems at an angle, just above a leaf node. Removing spent flowers (deadheading) encourages the plant to produce more blooms. As the first frost approaches in mid- October, harvest any remaining blooms to enjoy indoors.

Chrysanthemums can face a few common problems in the Great Plains. Here's how to identify and address them:

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).

Spider Mites *What it looks like:* Fine stippling on leaves (tiny white dots). Fine webbing on leaf undersides and between stems. Leaves turn bronze or yellow. *What causes it:* Tiny arachnids that thrive in hot, dry conditions. Populations explode in drought stress. *How to fix/prevent it:* Strong water spray (daily for a week) is the best treatment. Increase humidity around plants. Neem oil or insecticidal soap. Release predatory mites (Phytoseiulus persimilis). Avoid broad-spectrum pesticides that kill predators.

Leaf Miners *What it looks like:* Tan, winding trails or blotches within the leaves. *What causes it:* Larvae of small flies that tunnel between the leaf surfaces to feed. More prevalent during periods of rapid growth. *How to fix/prevent it:* Remove and destroy affected leaves. Use row covers to prevent adult flies from laying eggs. Neem oil can deter egg-laying. Spinosad is effective against larvae inside the leaves.

Rust *What it looks like:* Rusty orange, yellow, or brown pustules on leaves and stems, mostly on undersides. Leaves yellow and drop prematurely. *What causes it:* Various rust fungi that spread via wind-borne spores. Favored by warm, humid conditions with moisture on leaves. *How to fix/prevent it:* Remove affected leaves. Avoid overhead watering. Improve air circulation. Apply sulfur or copper fungicide. Don't work among wet plants. Rotate crops.

Great Plains Specific Challenges: Our hot heat, low-to-moderate humidity, and variable rainfall can exacerbate these problems. Spider mites thrive in dry conditions, while rust can become an issue during periods of humidity. Consistent monitoring and prompt action are key to keeping your chrysanthemums healthy. Wind protection is essential too; a sheltered location will reduce stress and pest issues.

Chrysanthemums benefit from companion planting in the Great Plains. Tomatoes and peppers make good companions because they provide some wind protection, which is essential here. Lettuce planted nearby can act as a ground cover, helping to retain soil moisture during our hot summers. Avoid planting chrysanthemums near , as they can compete for nutrients and water, especially during dry spells.