Skip to Content

When Do Mums Bloom? (And How to Make it Happen)

When Do Mums Bloom? (And How to Make it Happen)

Share this post:

Disclaimer: Some links found on this page might be affiliate links. If you click an affiliate link and make a purchase, I might earn a commission. As an Amazon Associate I earn from qualifying purchases.

Nothing screams fall like the lush blooms of chrysanthemums, or mums for short. And you’ll often find them in the seasonal lineup long before summer is over.

But when exactly do mums bloom? How do you trigger their flowers and keep them blooming for longer?

Well, I’m not keeping mum about it any longer, so read on!

When Do Chrysanthemums Bloom?

Chrysanthemums are a big family with around 40 species, plus countless hybrids or cultivars. It’s no wonder that different varieties flower at various times.

Now, most mums are fall bloomers and start flowering in September.

Early blooming mums might flaunt their flowers in late July, while some fashionably late mums won’t bloom until October.

So, don’t forget to ask your garden supplier about your plants’ flowering schedule so you can pamper them right.

How Long Does It Take for Mums to Bloom?

If you’re starting mums from seeds, expect their vibrant flowers in the first year after planting.

During their reproductive stage, mums won’t set buds until nights last for 10 hours. You’ll find soon enough that chilly temperatures equal fresher, more colorful flowers.

The best part?

You get to enjoy them for up to eight weeks. It turns out the cold never bothered mums anyway!

What Triggers Mums to Bloom?

Mums are what you call short-day plants. They’re wired to start blooming when the days get shorter, usually from September until the first frost.

Shorter daylight hours help them prepare for the changing seasons, like flipping the switch from vegetative to reproductive growth.

How Do You Keep Mums Blooming?

Watering Chrysanthemums

Flowering mums can give you pure bloom bliss for around 4–8 weeks. But with a bit of extra TLC, you can nudge them toward the longer end of that timeframe.

Here’s what to do:

1 – Deadhead Your Mums

The trick to keeping your mums blooming all season? Deadheading.

It’s basically getting rid of those tired, old flowers. You can pinch the flower head at the base or use pruning shears.

While you’re at it, clear out those dried leaves and dead stems as well.

When you deadhead your mums, you’re stopping them from wasting resources on spent flowers. Instead, that energy can go into the buds just waiting to pop open.

Plus, your mums will look much tidier if you make deadheading a routine.

2 – Pick the Right Mum

It’s hard to resist grabbing those mums from the garden section, especially when they’re practically exploding with blooms. And let’s be honest, it’s even more tempting if they’re on sale.

But if you want your garden or front porch dressed in fall colors all season, pick a plant loaded with tight buds that haven’t popped open yet.

This way, you’ll witness the entire floral spectacle right from the very start.

3 – Let Your Mums Bask in the Sun (But Not Too Much)

Mums love soaking up the sun during their growing season. They thrive when they get a solid six hours of sunlight daily.

If you’re in an area with scorching summers, place them in a bright spot away from direct sunlight. Heat waves can cause leaf burn in mums, so watch out for crispy, browning, or curling leaves.

4 – Keep Your Mum Hydrated

Established mums can get by with a weekly drink. On the other hand, younger plants just starting to bloom need more frequent hydration to encourage larger and brighter flowers.

You’ll want to water these beauties every other day. If in full sun and it’s too hot, water them daily.

Use a gardening hose or watering can without the spray nozzle to get underneath the thick bush. Push back the foliage gently and water the soil until thoroughly soaked.

Proper watering should help keep the mums healthy and ready to bloom. If you don’t water them enough, the blooms won’t be as vibrant as they should be.

 5 – Feed Your Mums

Mums can bloom without fertilizer, but if you want bigger and bolder flowers, consider giving them some plant food in early spring.

Try feeding them every two weeks until you see those little buds. I recommend sticking to 6-2-4 or 4-2-3 fertilizers.

What Happens to Mums After They Bloom?

Potted Chrysanthemums

Mums are hardy perennials in USDA zones 5–9 and will go dormant all winter. Some mums might even rebloom if the temperature isn’t too harsh.

When resources are scarce, they’ll stop growing to conserve their energy. Don’t worry; they’ll perk up when the weather becomes warmer again.

Anywhere else too cold is inhospitable for perennial mums, especially in zones 4 and below. In such cases, opt for annual mums instead.

If your mums don’t survive the winter, you can simply toss them in the compost pile.

Meanwhile, trim back your post-bloom garden mums by cutting off the faded flowers and spent foliage. You must remove about one-quarter of their height.

Do Potted Mums Come Back Every Year?

Many mums you’ll find in gift pots from nurseries and garden centers are florist mums, which have fewer or no stolons. Stolons are ground-level runners that sprout new roots and shoots.

Unlike garden mums, florist mums usually don’t make it through the winter. They grow in greenhouses with a pampered lifestyle, making them finicky about temperatures.

Feeling brave? You can transplant potted mums into the ground about six weeks before the cold weather hits hard. Your mums should establish roots as long as the soil is still warm and a bit damp.

There’s a slim chance they might return for a repeat performance, especially those with stolons. But hey, don’t put all your bets on it!

Can You Force Mums to Flower?

Pinching Chrysanthemums

Ever wondered why you can buy a blooming mum any time of the year? The secret is exposing mums to less daylight and more time in the dark.

You can make mums blossom early in a controlled environment, like a greenhouse. Alternatively, you can use a blackout curtain to trick your mums into thinking it’s fall, even in the middle of summer.

Here’s another tip: Stress your plants by slightly reducing watering. It can sometimes trigger mums to develop crown buds (premature flowers) as a survival mechanism.

Be careful not to let the soil dry out completely, as mums still need adequate moisture. And remember, crown buds can stunt plants.

That said, not all mums will play along the same way. Different varieties may have varying responses to environmental cues.

Some cultivars are responsive to forced flowering in controlled conditions, while others may be less predictable.

Frequently Asked Questions

Do Mums Bloom in the Summer?

While many mums are known for their showstopping fall display, some decorative mums can burst into color as early as the summer.

What Do You Do With Potted Mums After Blooming?

Once your potted mums finish blooming, it’s best to move them outdoors. If you notice a few good-looking stolons, you can replant them in a flower bed or as a border for your garden.

Then, provide them with the right conditions and care for a flourishing encore next season.

Why Do My Mum’s Flowers Keep Dying?

There could be a few reasons for this floral mystery. Check the basics, such as sunlight, water levels, and soil quality.

Overhead watering can also cause the blooms to die back faster.

Final Thoughts

Knowing when mums bloom makes garden planning a breeze. Most bloom in the fall, but some may surprise you by flowering in the middle of summer.

If you’re buying mums to plant, ask your garden supplier about their blooming habits.

Share this post: