Forcing Branches

– Posted in: Experiments, Forsythia, How-to, The Earliest Flowers
5 comments

Forcing branches of flowering shrubs and trees is a skill I try to get better at every year–it’s another way to hurry spring up. Compared to last year, this winter has been more consistently snowy and cold. It hasn’t been severely cold, but we haven’t had the intermittent thaws that we had last year.

But for the last week, the temperatures have moderated. Almost every day has managed to get above freezing, which makes me think it’s time to start forcing branches.

How do you force branches?

The basic concept is simple: cut branches of flowering shrubs and trees, bring them into the house, and let the warmer indoor temperatures coax the branches into early bloom. But the devil is in the details!

When do you cut the branches?

Most articles about this topic say as long as you’ve had at least 8 weeks of temperatures under 40°F (4.4°C), you can cut branches anytime. Most articles also say wait for a day when the temperature is above freezing. In my cold climate, I prefer to wait until we’ve had a week of temperatures above freezing–ideally 40°F or above. That’s because those flower buds have been chilled for months (not weeks) and I like them to get a hint of spring in their system before I bring them indoors.

Other people say if you soak the entire length of the branches in water for 24 hours, it will overcome the effects of a prolonged cold season. The only place suggested for this soaking is a bathtub. Maybe you have a bathtub to spare, but I don’t want to risk finding out what happens if I put a “bunch of sticks” in the tub where family members get ready to go to work. So, I wait until we’ve had a thaw before going out to cut.

Most articles on this topic that I’ve read assume a shorter winter than what I have. This schedule from the Vermont Cooperative Extension is more realistic for cold climates, but even they suggest to start cutting earlier than I do. Experiment to see what works best for you.

What kind of branches do you cut?

Any early-blooming or -budding woody plant is fair game. It depends on what is growing in your garden. It helps if it needs pruning anyway.

forsythia forced indoors
I forced this forsythia last year.

Forsythia is my first choice. It blooms readily indoors; it usually needs thinning; and I love that sunshine yellow. Since it blooms so early outdoors it’s not that far from blooming when you bring it indoors. The trick is to make sure you are trying to force branches that have flower buds on them.

forsythia leaf buds and flower buds
Both leaf buds and flower buds on forsythia are pointy.

In my experience, the newest growth only has leaves. You want branches that are at least two years old. If you look closely at a branch, you will see two different kinds of buds. The plumper ones are the flower buds. In the photo above, you can see they are already starting to open. The leaf buds are narrower and have scales.

Of course you want to cut branches that have lots of flower buds, but also need to come out for aesthetic reasons. But the old branches that need to be pruned out are typically not the ones with lots of flowers, so choices must be made.

flowering quince forced indoors
Flowering quince, also from last year. The color of outdoor flowers is more intense. This is Double Take Orange™ (Chaenomeles speciosa ‘Orange Storm’ ) from Proven Winners, which I received as a sample plant a decade ago.

I’ve also forced flowering quince. The first year I tried, the branches never bloomed. The buds swelled, but never got any further than that. Eventually they started to brown and drop off, and the branches started to leaf out.

flowering quince buds
Here’s what flowering quince buds look like.

I decided I had cut them too soon, so last year I waited longer before I cut them. As with the forsythia, I cut branches that needed to be pruned anyway. In this case, the branches were hanging over a parking area, so they were not the oldest branches and had lots of flower buds. I was surprised to see the flower color was much paler than usual, and I actually liked it better.

The same flowering quince out in the garden!
daphne mezereum forced indoors
“February” daphne–which blooms in late March or early April for me.

My February daphne (Daphne mezereum) has not really grown big yet, and normally I wouldn’t consider cutting branches. But I wanted to limb it up so I could plant primroses and bulbocodiums at its base. Of course I forced the branches.

Other plants (which I haven’t tried myself) include Cornelian cherry, witch hazel (spring blooming types), poplar, willow, red maple, alder, Juneberry, apple and crabapple, birch, and cherry. Again, start with what you have, or what a neighbor gives you permission to cut.

If you followed good pruning practices, you will probably have cut larger branches with many side branches. Before going back inside, look everything over to see if you can make further cuts so you are bringing smaller branches with the most flower buds into the house.

What do you do after you cut them?

You treat them like any other cut flower, but you have to wait longer for the pay off.

  • Use clean water and a clean vase. Choose a vase that is large enough to hold the branches and won’t tip over.
  • Cut the ends of the branches under water, making two cuts perpendicular to each other (like a cross) so that you increase the surface area available for water uptake.
  • Place in a cool room away from direct sun. And wait. It typically takes a couple of weeks, but could take longer if the buds aren’t very advanced.
  • Replace the water every couple of days or whenever you see it get cloudy.
  • When the buds start to open, pat yourself on the back! You can bring the arrangement into a warmer room (so you can see them as you go about your daily tasks) but they will deteriorate more quickly if you do.

A few last words . . .

The best way to get started is to stick whatever you’ve just pruned into a bucket or vase of water and see what happens. As you can see from the list above, even trees that you might not think of as “flowering” can provide some interest. The worst that can happen is . . . nothing. A bunch of sticks in water remains nothing more than a bunch of sticks in water.

But even if they don’t flower, your prunings may leaf out, weeks before they would do so outside. It’s a little bit of spring indoors and it can be addicting. Before you know it, you’ll be eyeing your garden for what else you can cut, and choosing new woodies for your garden based on how easily they can be forced. I planted a variety of willows known for attractive catkins last year for just this reason.

Want to learn more?

These websites inspired and encouraged me.

From Dormant to Delightful

Forcing Flowering Branches for Winter Blooms

Forcing Flowering Branches

About the Author

Kathy Purdy is a colchicum evangelist, converting unsuspecting gardeners into colchicophiles. She gardens in rural upstate NY, which used to be USDA Hardiness Zone 4 but is now Zone 5. Kathy’s been writing since 4th grade, gardening since high school, and blogging since 2002. Find her on Instagram as kopurdy.

In its own way, frost may be one of the most beautiful things to happen in your garden all year . . . Don’t miss it. Like all true beauty, it is fleeting. It will grace your garden for but a short while this morning. . . . For this moment, embrace frost as the beautiful gift that it is.

~Philip Harnden in A Gardener’s Guide to Frost: Outwit the Weather and Extend the Spring and Fall Seasons

Comments on this entry are closed.

Tim C March 4, 2021, 11:01 am

Peach tree prunings also force well. To aid in getting buds to break, have had some success wrapping the branches in damp newspapers and a plastic bag. Inspect every couple of days to avoid mold developing.

Kathy Purdy March 4, 2021, 5:21 pm

Yes, many fruit tree branches can be forced. Thanks for the tip about newspapers and a plastic bag!

Layanee DeMerchant March 4, 2021, 8:37 am

Such loveliness! I will have to go take a walk and see what might be ready for the vase! Thank you for the inspiration.

Christine March 4, 2021, 4:17 am

This is very interesting and I will certainly try next year. I’ve had totally unintentional success with bare branches that were used for structure in winter arrangements – such a delightful surprise when you see the buds open!
But I have a question: daphne mezereum grows wild where I live so I planted some into my garden (the perfume!) but I read that it would die if pruned, so I daren’t touch it although I would like to change the shape of the bushes. Have you noticed any dire consequences when you pruned yours?

Kathy Purdy March 4, 2021, 10:21 am

Well, I pruned it early last spring and it grew normally all through the summer and into the fall. It’s too early for it to be blooming here, so I can’t tell you if it made it through the winter. I suppose any cut can make a plant more vulnerable to disease, and daphnes have a reputation for dying for no discernible reason. So perhaps that’s why that advice is given. If it’s easily replaceable I would try it.