As summer begins, ornamental growers are preparing for a successful mum season. However, warmer weather brings environmental challenges that can threaten outdoor mum production. Higher temperatures and increased moisture require a proactive approach to minimize insect and disease pressures, ensuring plant quality and attractiveness throughout the season.

Set the Stage for Success

For successful production and plant quality, prepare your operation early-on to manage risks with these tips:

• Choose the right site: High temperatures, direct sunlight and oversaturated soil can increase disease risk. Select a growing location that helps mitigate these conditions throughout the growing season.
• Prioritize sanitation and drainage: Start with clean production areas, level ground and well-drained soils. Irrigate early in the day to prevent overnight moisture buildup.
• Use elevation when needed: Elevating plants off the ground can improve airflow and reduce exposure to soilborne pathogens.

Understand the Pressures

Root and stem diseases, particularly those caused by Pythium and Fusarium species, are common threats to garden mums, especially under warm, moist conditions. These pathogens weaken plant health and can significantly reduce quality if not addressed early.

• Pythium spp. infections are more prevalent in southern regions with frequent, heavy rainfall and high temperatures. Infected plants often appear pale green, stunted and wilt during the hottest part of the day—even when soil moisture is adequate. As the disease advances, lower leaves yellow and drop.
• Fusarium spp. typically becomes visible in late summer, but infections begin much earlier. Symptoms include pale foliage in sections of the canopy and wilting that starts at the base and moves upward. Season-long protection is key.

In all stages of production, garden mums are highly susceptible to thrips, aphids and worms.

• Aphids feed by piercing plant tissue and extracting sap, reducing vigor and causing leaf discoloration, curling or loss. Both adults and nymphs can cause significant damage.
• Thrips are tiny insects that scrape and suck sap from leaves, buds and shoot tips. Damage appears as silver streaks (stippling), scarring or deformed growth.
• Lepidopteran pests such as loopers and armyworms can quickly damage terminals if not caught early. Monitor for moth activity and apply timely controls to prevent feeding damage.

Build a Strong Agronomic Program

An effective agronomic program for mums should include trusted solutions like Mainspring^® GNL insecticide. Rotating products with different modes of action helps prevent plant stress and damage while maximizing protection.

Mainspring GNL is a systemic insecticide from the diamide class, offering long-lasting control through spray or drench applications. This flexibility allows you to target insects throughout the plant, including on leaves, in the canopy and around the root zone.

When used preventively, Mainspring GNL works by stopping insect feeding upon ingestion. This rapid action paralyzes insects, preventing disease transmission and avoiding visible damage to foliage and flowers. It is effective against key pests throughout mum production, including:

• Thrips
• Aphids
• Lepidopteran insects such as loopers and armyworms

Preparation is essential to successful insect and disease management—and Mainspring GNL is a valuable tool in any proactive strategy.

To learn more about building an agronomic program to help grow healthy, attractive mums, visit GreenCastOnline.com/Solutions.

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