After receiving tons of questions about chrysanthemums (or mums for short) each fall, we want to reveal how to care of mums as well as all the other information you've always wanted to know about this beauitful fall plant.
If you do a web search, you'll be faced with different and conflicting information so we want to clear up the confusion once and for all.
We all see mums in nurseries and garden centers in many different pots around September each year, welcoming the start of a new season. You'll see different yellows, oranges, purples and various flower types, each having it's own unique characteristics.
In addition, if you look around home landscapes, you'll also see mums blooming in gardens too and if you're like us, you want some in your own gardens as well, coming back and blooming every year.
The question them comes, how to care for mums in the ground as well as in pots. Can I take my pot of mums and plant them in the ground after they've bloomed in the fall? Will they come back every year? Are mums annuals or perennials? So many questions.
Here, my friend are the final answers and everything you need to know that will finally answer the question of how to care for mums.
Varieties Of Mums
There are many varieties of mums out there, most are named by the color of their blooms.
However, the best way for you to classify mums are based on only 2 different types - hardy versus non-hardy plants - more commonly known as florist and garden mums. You should know about each one because each needs to be treated differently.
We'll start with the florist type of mum.
This type has been cultivated to be used by florists or sold in stores that might have a small flower department but hardly qualify as garden centers. Places such as grocery stores or drug stores fall into the category. Plants sold in pots in these places are are not hardy and cannot be planted in the ground in most climates. Therefore they are considered annuals.
It's not unusual that if you see mums in places that are NOT flower or garden related you will not see a plant tag to identify what type of mum it is. In those cases, assume it's an annual that will need to be tosssed out once it's bloomed.
Here's a red flag - fancy foil wrapped pots. If you were in the hospital and someone brought you a mum in a pot wrapped in foil, it's probably not the hardy variety.
For this article, we want to focus more on the "hardy" variety, or garden mum. You'll find these types in nurseries and garden centers, including big box stores.
In these places the variety may be identified so you know for sure. In fact, as of this writing, Home Depot is selling mums identified on the plant tag as... "Garden Mum Red" or "Garden Mum Yellow" etc.
If you don't know, ask an employee to be sure.
Garden mums will come back and bloom year after year. However, they need some specialized care to really reach their potential - but don't worry. Even if you leave them alone and give them no care at all they will still bloom.
The only thing you may need to help mother nature with is water - that's if you're having an exceptionally dry year.
This is an image of a mum that is blooming now, as we are writing this article - Sept. 29, 2021 and came back from a mum that was purchased in a pot at a big box store and thrown away by a client.
We didn't plant it there. It's just taken root. Proof that they can look good even if left to their own devices.
Planting Zones For Garden Mums
Knowing how to care for mums means first, knowing if you can even grow them.
Garden mums are perennials in zones 5-9. You'll notice we didn't say warmer zones such as 10 and above. This is because they prefer colder weather and would not survive in the heat.
In addition, planting in a climate that's too cold might mean they won't come back either. Even if you live within the specified planting zones, if you get a winter that's exceptionally cold and harsh, they might not come back.
Generally though, when planted in the ground within the these zones, they should come back year after year.
Are Mums Full Sun?
To do best, mums do best in full sun but they will grow in partial shade too. However, full shade would not be good for the plant.
Generally, the more sun they get, the better they will do.
When Should You Plant Mums?
You may have heard that you cannot plant pots of mums in the ground after they've bloomed in the fall.
This is not necessarily correct.
If they are florist mums, as we mentioned above, yes, you cannot plant them because they are annuals.
If they are garden mums but finished blooming too close to your first frost date, you also cannot plant them, but if planted early enough, you can.
Let us explain.
In order to survive their first winter in the ground, garden mums need to be planted early enough so that the roots can start to establish themselves in the ground before it freezes.
Because of this, you'll often hear advice that planting mums in the spring is best and we say, if you can find them, sure plant them then.
However, for most of us, we're purchasing mums in the fall. The good news is you can plant them in the fall and they will usually come back, depending on how early you plant them and when your climate starts to turn the ground cold.
This can be tricky - mainly because of the fickle weather patterns we have today. As you're probably aware, in many years the weather does not follow the yearly averages.
For instance, if your first frost is forecasted for Oct. 21st but this year it came Oct. 8th, your mums might not make it if planted in the middle of September.
The same holds true for a warmer than normal beginning of winter. You'll have a much better chance of them coming back.
So, let's say you've purchased potted garden mums at the beginning of September and you want to keep them on your deck in pots. Then let's say they are finished blooming the 3rd week of September. If you plant them soon after blooming, they'll most likely become permanent perennials in your garden if you live in moderate climate zones. The colder your zone, the sooner they should be planted.
If however, you're busy and wait until the end of October to plant, they may not have sufficient time to get established before the winter chill sets in. In that case, they might not survive.
As you can see, due to weather it's a bit of a crap shoot as to whether your mums will come back or not... but here's the solution.
If you want mums in your garden, purchase potted garden mums as early in the season as possible and plant them in the ground immediately. Don't wait for them to finish blooming.
If you're purchasing garden mums in order to display them in pots elsewhere, then either consider them annuals and toss them once they finish blooming or plant them once they finish blooming and hope they come back next year.
How To Plant Mums In The Ground
Chrysanthemums, like most plants, are very easy to plant in the ground. When planting mums, simply did a hole equal to the depth of the pot and 1 1/2 times as wide. Remove the plant from it's pot and stick it in the ground with the top of the root ball level with the top of the ground.
Fill the hole with a combination of native dirt you dug out, plus some peat moss and compost or other nutrient rich soil.
As is the case with all plants, do not bury the top of the root ball in soil, which can hurt the plant.
How Long Do Mums Last?
Unfortunately the blooming time of mums is short - only a few weeks - which is such a shame for such a beautiful plant.
This is why it's best to purchase them BEFORE they bloom; that is, just budding. In this case, you'll get to experience their full blooming cycle.
If you make the mistake of purchasing them when the blooms are already open, you won't know when they started blooming, which means you won't know how long those blooms will continue.
Because of this fact, it's possible that when purchasing mums in full bloom they will start to fade not long after you purchase them and that's a bummer.
Always purchase mums that are just budding or where a few flowers have just started to open.
How Do You Take Care Of Mums?
Most people that have questions about how to care for mums are usually talking about cutting them back. Indeed, for the best blooming, it's recommended that they but cut back approximately 3 times during the summer.
Cutting mums back in summer means they will most likely form that large ball you see in the nurseries and their blooms will be more numerous and large.
Best practice says to trim them back 3 times per year - usually when they reach about 6 inches tall. The dates that are often used are St. Patrick's Day, Mothers Day, and The 4th Of July..
After the 4th you'll want to leave them alone.
Many people have heard that they need cutting back and assume that if they don't do this, they won't bloom. Nothing could be further from the truth.
If you don't trim them back during the year, you'll still have blooms in the fall but also, the plant may bloom earlier too. However, the flowers might not be as numerous or showy - but - that isn't always the case either. We've seen first hand mums bloom beautifully that have been left totally alone. (see the image above for proof of that).
Once they are finished blooming in the fall, you can then cut them back to the ground and look forward to them poking out of the ground the following spring.
Don't you just love the gardening world, where nothing is black and white, but filled with gray areas? We know, it's filled with multiple colors too, which is a good thing.
How To Care For Mums - The Conclusions
So the bottom line and things to keep in mind when shopping for mums...
- Do you want to plant them in the ground after they bloom. Look for a garden mums.
- Do you want to use them as potted annuals that will be disgarded? Either type will be fine, since it doesn't matter if they are hardy or not.
- Remember to cut them back 3 times per year for the best blooms in the fall.
Follow these rules of thumb and you'll know how to care for mums and be able to enjoy them in your gardens every year without having to purchase new plants.
To find our more about plants that will give you pleasure - visit our PLANT GUIDE.
If you need help with your fall gardens, prepping them for winter, or any other questions about gardening, you can ask us questions by joining us here!
Finally, learn more about pests and diseases that affect mums by going to the penn state extension agency here: https://extension.psu.edu/chrysanthemum-diseases