Should hummingbird mint be cut back?

Hummingbird mint (Agastache rupestris) is a popular perennial plant that attracts hummingbirds, butterflies, and bees to gardens with its nectar-rich, tube-shaped flowers. As the weather cools in fall, hummingbird mint dies back and goes dormant for winter. This leads many gardeners to wonder: should I cut back my hummingbird mint for winter?

When to cut back hummingbird mint

The optimal time to cut back hummingbird mint is in late fall after it has gone dormant. Here are some tips on when and how to cut it back:

• Wait until the plant has died back completely and turned brown. This usually occurs after the first hard frost.
• For many gardeners, late November or early December is the perfect time. But it depends on your climate and first frost date.
• If leaves are still green, wait to cut back until they have browned as well.
• Deadheading flowers during summer and fall is recommended, but leave the main plant intact until late fall.

Cutting back too early while the plant still has green growth can damage it. Waiting until it is fully dormant reduces the chance of winter injury.

Why cut back hummingbird mint

Here are some of the key reasons for cutting back hummingbird mint in late fall:

• Aesthetics – Removing dead growth improves the winter appearance of the garden bed.
• Tidiness – Cutting back creates a cleaner look for the dormant season.
• Pest and disease control – Removing old foliage removes overwintering sites for pests and fungal spores.
• Encourages new growth – Cutting back removes last year’s dull growth to allow fresh new foliage in spring.
• Prevents self-seeding – Cutting off spent flower spikes prevents unwanted reseeding around the garden.

Cutting back is an important garden maintenance task for hummingbird mint. The steps involved are simple and take just a few minutes per plant.

How to cut back hummingbird mint

Here is a simple step-by-step process for cutting back your hummingbird mint in late fall:

1. Wait until the plant is completely dormant and brown after frost.
2. Cut the stems back to about 2-3 inches above the ground.
3. Use clean, sharp pruners or garden shears for a clean cut.
4. Remove all dead leaves and debris around the base of the plant.
5. Discard the cuttings – they can go in your compost pile.

That’s all there is to it! Cutting back prepares hummingbird mint for winter dormancy and sets it up for vigorous new growth in spring.

Should I cut back all the stems?

Yes, it’s best practice to cut back all of the dead hummingbird mint stems in late fall rather than leaving some behind. Here’s why:

• Removing all old, brown foliage tidies up the appearance of the garden bed.
• Any pests or diseases lingering on the spent stems are discarded.
• New shoots emerging in spring will grow in more uniformly.
• You prevent self-seeding around the bed.
• Any woody buildup is removed, rejuvenating the plants.

Leaving behind old stems defeats the purpose of cutting back hummingbird mint for winter. For best results, make sure to cut back all the way to the ground level.

Should I cut back to the ground?

Cutting hummingbird mint all the way back to ground level in late fall is recommended. Here’s why:

• It removes all dead foliage from view.
• The bed is neatly tidied for winter.
• Any pests or diseases harboring on old stems are eliminated.
• Plants are rejuvenated by removing old wood and growth.
• New growth emerges uniformly in spring.

Cutting to the ground does not harm the plant – hummingbird mint readily regenerates from its crown below soil level. Leave 2-3 inches if the ground often freezes where you garden. Otherwise, cutting back to soil level is fine.

Will hummingbird mint come back if cut to the ground?

Yes, hummingbird mint will readily regrow after being cut all the way to the ground. Here’s why:

• The plant has a perennial root crown that survives below ground.
• New shoots will emerge again from the roots in spring.
• Cutting to the ground mimics the natural dieback in winter.
• Removing old foliage encourages fresh, new regrowth.

As long as the crown remains undamaged, cutting back to the base will not harm the plant. Hummingbird mint evolved the ability to cope with dieback each winter. Have confidence that your plants will resume growth once temperatures warm again.

Should I cut back if it still looks good?

Even if your hummingbird mint still has nice green foliage, it is best to cut it back in late fall. Here’s why:

• Leaving old foliage increases pest and disease carryover.
• Prevents the neat appearance of winter dieback in the garden.
• Risks damage if foliage is still green when frost hits.
• Old wood leads to reduced vigor compared to fresh new growth.
• Cutting back removes self-seeded plantlets around the mother plant.

The benefits outweigh any downsides. Follow the natural cycle by removing even healthy looking growth, and you will see even stronger plants next spring.

Should I cut back if dieback is partial?

If your hummingbird mint has only partially died back, it’s best to cut back all the way for winter. Reasons include:

• Partially cutting back creates an untidy appearance.
• Pests and diseases may remain on untouched stems.
• Removing only dead parts risks damaging living tissue.
• Uniform regrowth will be stronger in spring if you cut back fully.

Rather than selectively pruning just parts of the plant, remove all old top growth for the cold season. This quick annual maintenance neatly prepares hummingbird mint for spring.

What to expect after cutting back

Here is what you can expect after cutting back your hummingbird mint for winter:

• Removal of all dead foliage down to the crown.
• A tidy, clean look to your garden beds.
• No regrowth until spring soil temperatures warm again.
• Emergence of fresh new shoots from the roots next spring.
• Reduced frost damage and winterkill risk.

The steps are simple, and the work pays off once your rejuvenated hummingbird mint resumes vigorous growth again next year. Cut back in fall for healthy, prolific plants.

Will hummingbird mint bloom if cut back?

Yes, cutting back hummingbird mint at the end of the growing season will not impact its ability to reflower and bloom abundantly next year. Here’s why:

• The flower buds emerge from new growth each spring.
• Cutting back triggers the plant to produce fresh, vigorous stems and foliage.
• Any inhibition of flowering would occur from not removing old wood.
• Bloom time is triggered by warming spring temperatures, not winter pruning.

Hummingbird mint evolves each season for prolific flowering. Winter dieback naturally removes old growth as part of this cycle. By cutting back yourself, you simply mirror this natural process.

When will it grow back?

You can expect your hummingbird mint to begin regrowing in early to mid spring. The timing depends on your local climate and conditions:

• Growth resumes once soil temperatures warm to around 50-60°F.
• This typically occurs in March to May, depending on your region.
• New shoots emerge from the plant crown at the soil level.
• Leaves unfurl and expand as the shoots reach 4-12 inches tall.

Hummingbird mint lies dormant over winter and timed its reemergence for the return of warmer weather. Be patient, and new foliage will be up before you know it.

Do I need to mulch after cutting back?

Mulching around your hummingbird mint plants after cutting back is highly recommended for:

• Protecting the crown from intense cold if you garden in very cold winter areas.
• Insulating the soil and roots from temperature fluctuations.
• Preventing early sprouting if you get unseasonal warm spells.
• Keeping weeds down around freshly cut-back plants.

Use 2-3 inches of shredded bark, leaves, straw, or other organic mulch. Ensure it does not touch the crown itself. Remove mulch in spring as new growth emerges.

Conclusion

Cutting back hummingbird mint in late fall as it goes dormant is recommended. Removing all old, dead foliage improves the plant’s winter survival and sets it up for vigorous new growth each spring. Follow the simple steps of:

1. Waiting until the plant has died back and turned brown after frost.
2. Cutting all stems back to right at ground level.
3. Discarding old cuttings and debris.

This quick annual task keeps your hummingbird mint looking its best. Allow it to naturally die back, then cut it to the ground once dormant. Healthy new foliage will emerge again next year.