Growing heirloom chrysanthemums offers a rewarding experience rooted in tradition and rich history. These flowers, cherished for generations, stand out in the floral industry due to their exceptional qualities as cut flowers. However, the introduction of new varieties has unfortunately led to the decline of many heirloom types, resulting in a loss of diverse cultivars that once thrived.

Recently, a revival of interest in heirloom chrysanthemums is gaining momentum among farmer florists and home gardeners alike. This resurgence is vital, as large commercial cut flower farms have not focused on preserving these unique varieties, and much of the specific cultivation knowledge has disappeared over time.

At our small farm in western Pennsylvania, we are dedicated to cultivating these beautiful flowers and are actively seeking to gather as much information as possible about each heirloom mum variety we grow. While we market our rooted cuttings as tender perennials, it is essential to note that these heirloom mums can thrive as perennials in USDA hardiness zones 6 through 9.

These chrysanthemums are remarkably sturdy and easy to cultivate, making them an attractive option for both novice and experienced gardeners. However, due to the lost insights into their adaptability, it is still uncertain how well they can survive and bloom in regions farther north without the protection of a high tunnel or greenhouse. Our goal is to ensure that the beauty and tradition of heirloom chrysanthemums continue to flourish for future generations.

An heirloom chrysanthemum rooted cutting ready to be planted.

Heirloom Chrysanthemum Planting Guide

Step 1: Spring Planting

Select the Right Location

Choose a sunny spot with well-drained soil. Ensure the area receives at least 6 hours of sunlight daily. Heirloom chrysanthemums bloom best if not planted near street lights or any outside lighting, as they are photosensitive. Short days and long nights will promote blooming.

Prepare the Soil

Amend the soil with organic matter, such as compost, to enhance drainage and fertility. This improvement aids the roots in spreading more easily, resulting in a stronger root system that helps the plant withstand winter conditions.

Choose Your Varieties

Select heirloom varieties that suit your climate and aesthetic preferences. If you are growing for production as a flower farmer or florist, consider varieties that will meet your customers' needs. Key considerations include:

The space available for growing these beautiful flowers.
The size of the plant you wish to cultivate, as some varieties can grow quite tall.
The purpose of the flowers—whether for show, events, market bouquets, or personal enjoyment.

Popular options include:

Freshly transplanted mum rooted cuttings in an unheated high tunnel.

Planting Transplants

Space plants 12-18 inches apart for optimal growth in a home garden. For flower farming, we plant using a spacing of 6 inches to encourage extra stem length.

Watering After Planting

Thoroughly water the plants after planting to help establish the roots. Maintain consistent moisture (avoiding sogginess) as the plants settle in.

Mums that are getting close to blooming.

Step 2: Growing Care

Watering Schedule

Water deeply once or twice a week, adjusting according to rainfall and climate conditions.
To prevent fungal diseases, avoid overhead watering and focus on watering at the base of the plants.
For high tunnel environments, drip irrigation is recommended to maintain consistent moisture levels.

Pinching Guide

Pinch or trim plants back every 2 to 3 weeks until the end of June.
This practice encourages plants to fill out and produces ample stems for harvest.

Fertilization

Apply a balanced fertilizer (10-10-10) weekly throughout the growing season to promote healthy growth.

Champagne Beauty growing up through the netting we use to support the mums as they grow.

Step 3: Support

Support may be needed as many mums grow tall. For the floral trade, straight stems are a must. In the home garden, a natural flowing look is beautiful. Consider using netting if necessary for support, based on your discretion and the specific needs of your plants. Proper care and attention to their growth habits will ensure a healthy and visually pleasing display.

Pest and Disease Management

Regularly monitor for common pests such as aphids and spider mites.
Use insecticidal soap or your chosen pest management method as necessary.
Ensure good air circulation around the plants to reduce the risk of fungal diseases and avoid crowding.

Mulching

Apply a layer of mulch to help retain soil moisture, suppress weeds, and regulate soil temperature.
In a high tunnel growing setting for mums, biodegradable plastic mulch has been effective for weed control and moisture retention.

Mums can grow very tall and large, by netting the plants, keeping them weeded, and pest free will be key factors for success.

Coral Charm mum harvested and ready to go into our market bouquets.

Step 4: Harvesting

Determine Harvest Time

Harvest blooms when they are one-third to one-half open, depending on the specific variety.

Cutting Technique

Use sharp shears to cut stems in the cooler morning temperatures.
Cut stems at an angle and remove all lower foliage and keep several leaves to enhance hydration.

Post-Harvest Care

Immediately place cut blooms in water to help prolong their freshness.
Store blooms in a cool spot away from direct sunlight until ready for display.

Mums mixed with eucalyptus in market bouquets for our customers in November.

Step 5: Winter Care

Preparing for Winter

After the first hard frost, cut back the stems to about 4-6 inches above the ground.
Remove any debris surrounding the plants to minimize the risk of disease.

Mulching for Protection

Apply a thick layer of mulch, such as straw, leaves, or shredded bark, over the roots. This will help protect them from freezing temperatures.

Container Care

For potted chrysanthemums, move the containers to a sheltered area or wrap the pots with winter insulation.
Water sparingly during winter, ensuring that pots do not dry out completely.

This is what one mum plant looks like after it blooms and starts to regrow for the next season. We dig all of our mums we grow and treat them as tender perennials on our farm. This is from one single cutting that was planted the end of May and then dug up in December.

Treating as a Tender Perennial

Dig up the plants and remove most of the soil, being careful to retain as much of the root system as possible. The new roots will be essential for regrowth in spring.
Pot the chrysanthemums to be overwintered in a greenhouse or treat them as houseplants.
Alternatively, store the roots in a cool, dry place that does not freeze until spring. Then, replant the chrysanthemums in the garden.

Spring Cleanup

In early spring, remove the mulch and debris once the threat of frost has passed.
Check for new growth to ensure successful dormancy and prepare for another growing season.

By following this step-by-step guide, you can effectively care for heirloom chrysanthemums.

A Basic Guide to Growing Heirloom Chrysanthemums