Chrysanthemum in Zone 9A — Texas

Chrysanthemums add a burst of color to your garden, especially when other blooms are fading. They're perfect for cutting and bringing indoors, and their late-season blooms mean you can extend the beauty of your garden well into the cooler months, providing a welcome contrast to the fading landscape after the Texas heat has taken its toll.

Our unpredictable weather can be a challenge, but with a bit of planning, you can enjoy beautiful Chrysanthemums. Our long growing season, nearly 300 days, gives you plenty of time to get them established and blooming before the first frost.

Starting Chrysanthemum seeds indoors is an option, but honestly, with our long growing season, it's often easier to buy established plants from a local nursery. However, if you're set on starting from seed, begin in mid December through early January, about eight weeks before you plan to transplant.

Use seed trays with a good seed-starting mix. Keep them warm and provide plenty of light, either with a grow light or a sunny window. Bottom watering helps prevent damping-off. Remember, spring comes early in Texas, so starting on time is important.

Transplant your Chrysanthemum seedlings outdoors from mid February through mid March, after the danger of a hard freeze has passed. Before transplanting, 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 well-drained soil. Keep an eye on the forecast, as we sometimes get late cold snaps, even in Texas. Buying established plants in fall is also a great option for instant color.

Consistent watering is key for Chrysanthemums, especially during our hot Texas summers. While rainfall can be unpredictable, you'll generally need to supplement with regular watering. Aim for about 1 inch of water per week, applied at the base of the plant to avoid wetting the foliage.

Use the finger test to check soil moisture: stick your finger about 2 inches deep into the soil. If it feels dry, it's time to water. Water deeply but less frequently rather than shallowly every day.

Signs of underwatering include wilting leaves and dry, crispy edges. Overwatering can lead to yellowing leaves and root rot. Mulching around your plants with a layer of organic matter helps retain moisture and regulate soil temperature, which is especially helpful during our extreme heat.

Pinching your Chrysanthemums is essential for getting those full, bushy plants with tons of blooms. Start pinching the growing tips every 2-3 weeks, beginning when the plants are about 6 inches tall.

Continue pinching until around July 4th. This encourages side branching and more flower buds. After July 4th, stop pinching to allow the flower buds to develop. As the first frost approaches in early December, you can cut back the foliage to ground level after it yellows.

You can expect your first Chrysanthemum blooms from late April through mid June, depending on the variety and when you transplanted. The flowers last for weeks in the garden, providing a long season of color.

Harvest the blooms for bouquets when they are fully open. Cut the stems at an angle, just above a leaf node. Removing spent flowers encourages continued blooming. As the first frost approaches, harvest any remaining blooms to enjoy indoors, as they won't survive a freeze.

Here are some common problems you might encounter growing Chrysanthemums in Texas:

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 inside leaves.
• What causes it: Larvae of small flies that tunnel between leaf surfaces.
• How to fix/prevent it: Remove and destroy affected leaves. Cover plants with lightweight row covers to prevent adult flies from laying eggs. Neem oil can deter egg-laying. Spinosad is effective if applied when miners are active.

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.

Texas Specific Challenges: The hot-to-extreme heat and variable humidity of Texas can stress Chrysanthemums, making them more susceptible to pests and diseases. Consistent watering, good air circulation, and vigilant monitoring are essential for success. Fire ants can also be a nuisance, so keep them under control to protect your plants.

Chrysanthemums make great companions for several plants in your Texas garden. Tomatoes and peppers benefit from having Chrysanthemums nearby because the Chrysanthemums act as a natural insect repellent, protecting the tomatoes and peppers from aphids and other pests. Lettuce also benefits from the shade provided by Chrysanthemums during the hottest part of the day, preventing bolting.

Avoid planting Chrysanthemums near sunflowers, as they can compete for resources and attract similar pests.