How to Plant Fall Mums

Updated August 2026 · Garden Advice Guide

To plant fall mums, dig a hole as deep as the nursery pot and twice as wide, set the plant so the crown sits level with the soil surface, space plants 18 to 24 inches apart, and water deeply right away. Then water again the next day, and probably the day after that, because mums come out of the store badly root-bound and dry out faster than any other plant on the bench. Here's the part most guides skip: if you bought your mums in September in full bloom, they are almost certainly florist mums, which are bred as disposable annuals and rarely survive winter no matter what you do.

Check your window first: find your average first frost with our free frost date lookup so you know whether these mums have six weeks to root or six days.

That single distinction between florist mums and hardy garden mums is the honest answer to "why did my mums die." It's not your soil, and it's usually not your fault. Below is how to tell the two apart, how to buy the ones that last longest, and what your real odds are if you want to try overwintering anyway.

The two plants both sold as "mums"

Walk into a grocery store on September 10 and the cart by the door is stacked with mums in full bloom, cheap and in colors that look almost artificial. Walk into a good nursery in May and you'll find mums too, but they're small, green, unbranched, and labeled with a variety name.

Those are not the same product, even though both are Chrysanthemum x morifolium.

Florist mums (sometimes called cushion mums or hardy mums on the tag, which is where the confusion starts) are grown in a greenhouse on a tight schedule. Growers control day length with blackout cloth to force every plant into flower on the same week, feed them hard, and ship them at peak bloom. All of that energy goes into flowers instead of roots. The plant arrives with a shallow, congested root mass and no time left in the season to build a real one. It's engineered to look spectacular for four weeks and then be composted.

Hardy garden mums are the same species selected for winter survival and sold as small plants in spring. Planted in May or June, they spend the whole summer building roots and a woody crown. They bloom in September and October like everything else in the genus, and in zones 5 through 9 a good percentage come back. The University of Minnesota's chrysanthemum breeding program has released cold-hardy garden mum series specifically for northern gardens, which tells you how much of hardiness is genetics rather than gardening.

The rule that follows from this is simple, and it's the whole article in one line: if you want mums that come back, plant them in spring. If you're buying them in fall, buy them as decorations.

There's no shame in the second one. A grocery store mum that looks great from Labor Day through Halloween is a good deal, and it holds far longer than the same money spent on cut flowers. Just don't buy it expecting a perennial.

How to plant fall mums: picking a good plant at the store

The plant you carry out matters more than anything you do afterward. Three checks, thirty seconds.

1. Buy buds, not open flowers. This is the biggest one and almost nobody does it. A mum covered in open blooms is already halfway through its show. Look for a plant with color just breaking on the buds and plenty of tight green buds underneath. You'll get three to four weeks of display instead of one to two, from a plant that costs the same.

2. Check that it hasn't already dried out. Lift the pot. A mum that's light for its size has been dry, and a mum that has wilted hard even once will drop buds and brown its lower leaves later, on your porch, after you paid for it. Look at the bottom two inches of the plant. Crispy brown leaves down there mean it went dry on the truck or the bench. Put it back.

3. Check the roots, briefly. Tip the plant sideways and look at the drainage holes. Some roots showing is normal and fine. A solid white mat of roots growing out the bottom and circling the pot means the plant is at the end of what that container can support, and it will need water twice a day in warm weather.

Also look at the shape. You want a dome that's wider than the pot with foliage all the way down to the rim, not a tall plant with a bare bottom and flowers on top.

Watering is the whole game

If you remember one care instruction, make it this: a nursery-pot mum in September needs water every single day, and on a hot windy day it may need water twice.

That sounds excessive until you understand what's in the pot. There's very little growing medium left, because the root mass has replaced most of it. Water hits the surface, runs down the gap between the root ball and the plastic, and out the bottom in four seconds, leaving the middle of the root ball bone dry. Meanwhile the plant is carrying a huge amount of leaf and flower for that small volume of roots, so it transpires fast.

Here's what actually works:

• Water at the soil, not over the flowers. Wet blooms turn to mush and rot, especially in fall humidity.
• Water slowly, in two passes. Give it a slow drink, wait a minute for the medium to swell and close the gap, then water again until it runs out the bottom.
• Better yet, bottom-water. Set the pot in a bucket or tub with 2 to 3 inches of water and leave it for 20 to 30 minutes. The root ball wicks water all the way through. Once a week this way, plus daily surface water, and the browning stops.
• Check by weight, not by eye. Lift the pot each morning. Light means water. The surface can look damp while the core is dust.
• Punch out the decorative foil or take the pot out of the cachepot. A mum sitting in trapped water rots at the crown within days.

One dry-out is permanent. Mums don't recover the way a coleus does. Wilt a mum once and it responds by dropping buds and browning its lower leaves, and neither of those comes back. That is the single most common reason a fresh grocery store mum looks terrible after ten days.

Why mums brown from the bottom up

Almost always water, and almost always the two-pass problem above. The lower leaves are the oldest and the farthest from the top of the root ball, so they're the first to be sacrificed when the plant runs short.

The other causes, in order of how often they actually apply:

• Water sitting in a cachepot or foil sleeve. Roots suffocate, lower leaves yellow then brown, and it looks exactly like drought.
• No air movement. Mums packed shoulder to shoulder on a porch stay damp in the middle and develop leaf spot and botrytis. Give each plant a few inches of clearance.
• Normal aging. Late in the display a little bottom browning is just the plant finishing. Snap off the worst leaves and move on.

Planting potted mums in the ground

If you're planting rather than displaying, do it as soon as you get home. Every day the plant spends in that pot is a day it isn't rooting.

1. Water the plant in the pot first, an hour before you plant. Never plant a dry root ball.
2. Dig the hole twice as wide as the pot and exactly as deep. Width helps roots run sideways, which is where mum roots want to go. Extra depth just lets the plant settle too low.
3. Tease the roots. This one feels wrong and it's essential. The root ball is a solid circling mat, and if you plant it as-is the roots keep circling and never enter your soil. Score the sides in three or four places with your fingers or a knife, and pull the bottom apart.
4. Set the crown level with the surrounding soil. The crown is where stems meet roots. Buried crowns rot over winter, which quietly kills a lot of mums that people blame on cold.
5. Space 18 to 24 inches apart. Closer looks better for one season and creates the damp, stagnant conditions that cause disease.
6. Backfill with the soil you dug out. Skip the peat and the bagged amendment in the hole. A rich pocket in ordinary soil encourages roots to stay in the pocket.
7. Water deeply, a gallon per plant, then again the next day.
8. Hold the mulch for now. Mulch goes on after the ground freezes, not now. More on that below.
9. Skip the fertilizer. Fall-planted mums don't need a push into soft new growth right before frost. If you're growing hardy mums as perennials, feed in spring instead.

Full sun is what they want, at least six hours. Well-drained soil matters more than rich soil, and winter wet is a bigger killer than winter cold. A mum in a low spot that stays soggy in February is a dead mum even in zone 7.

Deadheading and display care

Snap or snip spent blooms off just above the first full set of leaves. It keeps the plant looking clean and pushes the remaining buds along. You're not going to get a second flush this late in the season, so this is cosmetic rather than productive, but it does add a week or so to how good the plant looks.

Deadhead in the morning when stems are firm and pinch cleanly rather than tearing, which leaves a ragged stub that browns.

For container displays, keep the mum in its nursery pot and drop that pot inside the decorative one. When it's finished you lift out the whole thing instead of digging out a rotting root ball. Raise it on a couple of stones so it never sits in standing water.

Are mums deer resistant?

Only moderately, despite what a lot of fall decorating articles say. Deer don't love mums, but a fresh pot of buds on a front step in October, when other browse is thinning out, is a real target. Gardeners in high-pressure areas lose mums regularly.

Treat them as "sometimes damaged" rather than safe, and put them where deer already don't go. If deer are a genuine problem in your yard, the reliably ignored plants are the aromatic and fuzzy ones, and our list of deer resistant flowers sorts them by how strongly they actually hold up.

Overwintering mums, honestly

You can try. Here's what it takes and what the odds really are.

The odds. In zones 5 and 6, a fall-purchased florist mum planted in early September, sited well, and mulched correctly comes back maybe half the time. Late September plantings drop well below that. Anything planted in October in a cold zone is a long shot, and the plant is better used as a decoration. Hardy garden mums planted the previous spring do considerably better.

Six weeks is the number. Roots need roughly six weeks of soil above about 50°F to establish before the ground freezes. Work backward from your average first frost. If you don't know it, our frost date lookup gives your county's date in a few seconds.

Water until the ground freezes. This is the step people quit too early. A dry root ball going into winter is the most common overwintering failure, and it happens in November when nobody is thinking about the garden. Keep watering deeply once a week through fall until the soil is genuinely frozen.

Leave the dead top growth standing. Do not cut it back. This is the opposite of what tidy fall cleanup says to do, and it matters. The old stems trap snow and leaves over the crown, insulate it, and keep the crown from being heaved out of the ground by freeze-thaw cycles. Cut mums back in November and you've removed the crown's blanket. Cut them back in spring instead, once new shoots appear at the base.

Mulch after the ground freezes, not before. The purpose of winter mulch on a mum is not to keep it warm, it's to keep the soil temperature steady so the plant doesn't get heaved. Mulch applied in October keeps the soil warm and wet, invites voles into the crown, and encourages rot. Wait until the top inch of soil is frozen, then put 3 to 4 inches of loose, airy material over the plant. Evergreen boughs, straw, or shredded leaves work. Skip heavy wet materials that pack down and hold water.

Pull the mulch back in early spring as soon as growth starts.

Spring care for the ones that made it

If green shoots appear at the base in April, you have a perennial. Three jobs:

Cut back the old growth to a couple of inches once new shoots are clearly coming. Now, not in fall.

Divide every second or third year. Mums die out in the center as they age. Lift the clump in spring, discard the woody middle, and replant the vigorous outer pieces 18 inches apart. This single job is why some gardeners' mums look better every year and others' fade out.

Pinch, and stop pinching on time. When shoots reach 6 inches, pinch out the top inch of each. Repeat every time growth adds 6 inches. Pinching is what turns a floppy leggy mum into the tight dome you paid for at the store, and it multiplies the number of flower buds.

The stopping date is the part that trips people up. Stop pinching by mid-July, or roughly July 4 in the coldest zones. Mums set flower buds in response to shortening days in mid to late summer, so pinching after that point removes the buds you were growing all year. Late pinching is the reason some gardeners' mums bloom thin, or not at all.

Worked example: zone 6, three mums, September 5

You're in zone 6b outside Cincinnati. Average first frost is about October 20. It's September 5 and you buy three grocery store mums, all with tight buds just showing color.

The math: October 20 minus six weeks is September 8. You are three days inside the window, which means overwintering is worth trying rather than hopeless.

• Sept 5, evening. Bottom-water all three in a tub for 25 minutes. Two go in the ground in the front bed, full sun, well-drained. One stays in its pot inside a decorative cachepot on the porch, on two stones.
• Sept 5, planting. Holes 18 inches wide, pot-depth deep, spaced 20 inches apart. Root balls scored on four sides and pulled open at the bottom. Crowns level with the soil. One gallon of water each, and again on the 6th. No mulch, no fertilizer.
• Sept 6 through Oct 20. Ground mums get a deep soak twice a week unless it rains an inch. The porch mum gets checked by weight every morning and watered most days, with a bucket soak every Sunday. Deadhead spent blooms weekly.
• Around Oct 10. The porch mum is finished. It goes in the compost, which was always the plan. One pot bought six weeks of front-door color, which is what it was for.
• Oct 20 to late November. Frost blackens the ground mums' tops. Leave them standing. Keep watering deeply once a week until the ground is frozen, usually late November here.
• Early December. Soil surface is frozen. Cover each plant with 4 inches of shredded leaves held down with a couple of evergreen boughs.
• Late March. Pull the mulch off. Watch the crowns.
• April. One of the two shows green shoots at the base. The other doesn't. That is a completely normal result and is roughly the 50/50 outcome you should expect. Cut the survivor's old stems back to 2 inches.
• May through mid-July. Pinch at 6 inches, then every 6 inches of new growth. Last pinch on July 12.
• September, next year. A mum that costs nothing, blooms three weeks longer than the store ones, and now has a real root system.

While the mums go in, September is the month for a lot of other planting too. Our zone-by-zone guide to what to plant in September covers the rest, and if you're adding spring bulbs to the same bed, when to plant tulip bulbs has the timing.

FAQ

Will my grocery store mums come back next year?

Usually no. Grocery and big box mums sold in full bloom in fall are florist mums, forced in a greenhouse and bred for a spectacular short display rather than winter survival. If you plant one by early September in zone 6 or warmer and mulch it correctly you might get roughly even odds, but the honest expectation is that it's an annual.

How do I know if I have a hardy mum or a florist mum?

Check when and how you bought it. A named variety with a USDA zone on the tag, bought small and green in spring from a nursery perennial section, is a hardy garden mum. A full-bloom dome bought in September labeled only by color is a florist mum, even if the tag says "hardy mum," which is used loosely in retail.

Should I plant my potted mums or leave them in the pot?

Plant them if you want any chance of them returning, and do it the day you buy them. Leave them potted if you're using them as seasonal decoration, since they're far easier to move, water, and replace that way. A potted mum on a porch will need daily water; a planted one won't.

Why are my mums turning brown at the bottom?

Almost always water. Root-bound nursery pots let water run down the sides and out the bottom without soaking the core, so the plant dries out even though you watered it. Bottom-water the pot in a tub for 20 minutes and check by lifting for weight rather than by looking at the surface. Standing water in a foil sleeve or cachepot causes the same brown look for the opposite reason.

How often should I water fall mums?

Daily in a nursery pot, and twice a day in hot, windy, or sunny conditions. Planted mums need a deep soak twice a week until the ground freezes. Skip a day with a potted mum in September and you'll likely lose buds and lower leaves permanently.

Should I cut back my mums in the fall?

No. Leave the dead top growth standing all winter. The old stems hold snow and leaves over the crown, insulate it, and prevent freeze-thaw heaving. Cut back to a couple of inches in spring once you see new shoots at the base.

When do I stop pinching mums?

Mid-July in most of the country, and around July 4 in zones 3 and 4. Mums set flower buds as days shorten in late summer, so pinching after that removes the buds instead of the growing tips. Start pinching when spring shoots hit 6 inches and repeat every 6 inches of new growth until your cutoff date.

Do mums need full sun?

Yes, at least six hours of direct sun, and more is better. In part shade they stretch, flop, bloom thinner, and hold moisture on the leaves long enough to invite leaf spot. Good drainage matters just as much, since winter wet kills more mums than winter cold does.

Updated August 2026

A note on numbers. This page gives you timings, zones, spacings and odds, not dollar figures. Mums are priced by the store, the pot size and the week of the season, and we do not set any of it. What matters here is which of the two plants you are buying, not what it rings up as.