Fertilizing Mums: An In-Depth Look

June 1, 2022
Category: Growing Tips

Today we’ll take an in-depth look at fertilizing mums. We’ll discuss how to both water and fertilize garden mums for vigorous, vibrant plants that will last. Let’s begin by talking about the best method for watering mums.

How To Water Garden Mums

When to Water

During the first few weeks after you transplant your rooted plugs, watering evenly and consistently will support a healthy root system. Water at the base of each plant early in the morning and keep the soil evenly moist in those first weeks. Garden mums grow primarily in the morning sun, so offering nutrition at the right time enhances growth. Early morning watering also helps prevent root rot and fungal infection, as the soil can dry out during the day rather than having roots sit in wet soil overnight. 

How Much To Water

Start with well-draining soil in containers that provide good drainage for extra water or feed to exit the pot. Water once, early in the morning, at the base of each plant. Keeping the foliage dry, the soil moist but not soggy, and plants drying overnight will help plants resist rot and infection.

You may notice wilting in the afternoon during the summer. For slight wilting in the late afternoon, leave the plants dry overnight and water them deeply the following morning. For plants dry in the early afternoon and already beginning to wilt, use clear, unfertilized water for a second watering. 

Application Methods

Commercial greenhouses have a few options for watering small to large crops of Garden Mums. While overhead watering is inexpensive and easy, we recommend investing in drip tape or drip tubes. 


This method involves employing automatic sprinklers or a person with a hose to water plants from above the foliage. It’s easy and cheap, but we discourage this method for commercial greenhouse use. Using sprinklers wastes water and fertilizer, and watering with a hose wastes labor. Overhead watering can damage blooms and nurture fungus by leaving foliage wet. We strongly recommend considering other methods.

Drip Tape

Drip tape is a cheap drip irrigation system intended for one-year use. While it is more expensive than overhead watering, it can be an entry-level irrigation system that offers most of the benefits of drip tubes. The method use connectors between flat drip line to deliver water or fertilizer to the soil level of each plant. Evenly spaced holes release water, and you can automate irrigation to avoid wasting water or fertilizer. Foliage and flowers stay dry by watering at the base of each plant, preventing infection and damage. 

Since this type of drip irrigation is intended to be used for just one year and then replaced, you may consider investing in a more expensive drip tube system that will last longer. The drip line needs to be maintained, especially during hot summers, as it can stretch out and dislocate the emitter sections outside your pots. While this system requires up-front time and money investment, it will increase the efficiency of water, fertilizer, and time in the long run. 

Drip Tubes

This irrigation method requires a significant investment but offers the best long-term benefits to your commercial greenhouse. Drip tubes use higher quality materials than drip tape and are to be installed and used permanently. You can install this system and employ it to distribute water and fertilizer for multiple crops all year waste-free. Automate irrigating and prevent damage and infection by feeding plants at the soil level. 

Long-term efficiency in water, fertilizer, and time use make drip tubes the obvious choice for any established greenhouse. If you’re considering using drip tape, find the extra money in your budget for this better-quality method to save installation costs in the future. 

How To Fertilize Garden Mums

What’s the best process for fertilizing mums? Superior mums result when growers feed in four stages with as much control as possible. 

Should You Use Slow-Release for Fertilizing Mums?

Slow-release fertilizers remove control over the feeding process and can release too rapidly and damage root systems, especially during high heat. We’ve moved toward a more controlled four-stage process for growing mums. When you use a slow-release fertilizer, you can’t control how much of a particular nutrient your plants receive at which point of development. Mums respond particularly well to certain nutrient levels during each development stage, rendering slow-release fertilizers suboptimal.

Though we discourage its use, we recommend that if you must use a slow-release fertilizer, you use a type that has a 3-4 month release at 6-12 pounds per cubic yard. Either combine it with your soil or use it as a top dressing and choose a newer brand that probably won’t release based on soil temperature alone. Pay close attention to pH and EC levels, running regular soil tests throughout the growing stages. 

Four-Stage Fertilizing

Controlled, precise fertilization is central to growing exceptional Garden Mums. Fertilize in four stages: root development, vegetative growth, bud development, and first color. As you closely attend to your plants, you’ll be able to key into a fertilizer program that excels in your climate for your particular rooted plugs. Check your soil pH and EC regularly to monitor whether your fertilizer delivered the nutrients your plants need. 

Root Development

Feed rooted liners just after transplanting. Use 250 ppm of 20-20-20 fertilizer or one similarly abundant in phosphor and ammonium-based nitrogen. Keep your plants growing by watering evenly without allowing the soil to dry out. 

Vegetative Growth

As week three of growth begins, use 300 ppm of a 20-10-20 fertilizer at the morning watering. If your plants are wilted by early afternoon and require a second watering, use plain unfertilized water. 

Generative Growth (Buds Developing)

As soon as you see buds developing, continue to use 250 ppm during the morning watering, but switch to a 15-5-30 fertilizer. High potassium encourages flower development.

First Color (Flowers Developing)

When you see the first color on your plants, stop fertilizing mums and use only plain water to support vivid bloom color.

Find even more information about succeeding from transplant to customer satisfaction with growing Garden Mums here. Explore our wide selection of mums, and please reach out to us with any questions.