Forcing Bulbs: A How-to Guide

Potted Bulbs

Bulbs that you force into bloom starting in the fall or winter keep summer around a little longer and excite our souls with the promise of the upcoming spring.  I love to watch them grow roots, sprout leaves and eventually produce the huge luscious blooms they create.  Forcing bulbs indoors in the winter months is very simple and always worth the tiny amount of prep time they require.

Different Flower Bulbs

The first step in forcing bulbs is to select your bulbs.  No matter what plants you will be forcing, it is important to choose the biggest and best bulbs available.  The biggest bulbs will produce the biggest size and number of blooms.  The bulbs should be firm and free from nicks or bruises.  Note that roots should not have sprouted either.

Bulbs in Refrigerator

Most bulbs require a certain amount of chill-time in the refrigerator before they can be forced.  Eight to fifteen weeks is the general requirement.  See the "Chill Chart" below for approximate chill-times for most bulbs.  You should, however, follow the package directions for any bulbs you purchase.  If you cut the chill-time short for any bulbs, you may get blooms, but they will probably be stunted or deformed.

Kitchen Hyacinth Huddle

When chilling bulbs in the refrigerator, the only concern is that there be no fruit in the refrigerator with them, especially not apples.  As fruit ripens (it continues to do so, even in the refrigerator), it gives off ethylene gas.  This gas can damage the flowers forming inside the bulbs.  It can even kill the flower and prevent any growth from occurring at all.  Using a garage or shed refrigerator is best, if you have one available.

Paperwhites

Two types of bulbs, paperwhites and amaryllis, do not need any chill-time.  They are warm climate plants and weren't bred where they were exposed to typical winter temperatures, so this period isn't necessary.  They can usually be planted right out of the package and will generally bloom about a month after planting.

Amaryllis

The easiest bulbs to force are the smaller ones, like crocus, hyacinths, muscari (grape hyacinth), and mini-daffodils, as well as the above-mentioned paperwhites and amaryllis. Tulips and standard daffodils can be forced, too, but require a little more careful attention.

Crocus

Hyacinth Bulbs Mix

Muscari (Grape Hyacinth)

Mini-daffodils

Standard Daffodils

Tulips

Bulbs force best in a wide, shallow pot that is 4 to 6 inches deep.  It should have a drainage hole and be at least twice as deep as the bulbs you are using.  You need to be sure you leave about 2 inches at the bottom below the bulbs to allow for root growth.  When you place the bulbs in the pot, make sure the pointy side is up and the root side is down so it will be able to grow properly.  Also, put the flat side of the bulb next to the rim of the pot as the largest leaf of the plant will always grow on that side.  This will produce a nicer-looking pot.   The very tops of the bulbs should be exposed and even with the rim of the pot. 

Ready for the Fridge

Additionally, potted bulbs look best when they are crowded, so snuggle bulbs together in the pot, but don't allow them to touch.  Leave about 1/2 inch between bulbs.  Generally, for a 6" pot, you should be able to plant 6 tulip bulbs, 3 hyacinths, 6 daffodils, or 15 crocus.  This will give you a nice, full-looking pot that looks like it is simply overflowing with floral beauty! 

Bountiful Bulbs

For an even thicker showing of blooms, layer more than one kind of bulb in the same pot. Obviously, you need to use a much larger pot to do this.  Depending on how may bulbs and how big they are, a 10" or 12" pot should work, provided it is either 10" or 12" deep, too.  Place the larger bulbs in the bottom (with the required 2" of root space), and the smaller ones closer to the top.  The larger flowers will grow around the smaller ones and all will bloom around the same time.  This works best if the bulbs you are using require the same amount of chill-time.

Cross-Section--Bulb Pot Growing

Once you have chosen your bulbs and your pot and determined how you are going to plant them, it is time to get them going.  Here are the steps you will need to follow to start forcing the bulbs.

1. Fill your pot with the required minimum of at least two inches of potting soil.
2. Place as many bulbs as possible in the pot, pointy side up, without allowing them to touch.
3. Cover the bulbs with potting soil, leaving the tips showing.
4. Water thoroughly.
5. Cover pot with a paper bag and place in the refrigerator for chill time.  This may be up to four months (see package directions), so make a comfortable space for the pot where it will only be minimally disturbed--preferably not at all.
6. Mark your calendar for when your chill-time is over.
7. At the end of this period, you should see roots poking out of the bottom of the pot and green sprouts emerging from the top.  This tells you it is time to move them into a cold room.
8. Wake bulbs up slowly from their chill-time.  After you remove them from the fridge, place them in a cool room in indirect sunlight where temperatures are around 55-60 degrees for about two weeks.  Keep the soil damp, but not wet.  This is how they should be watered from now on.
9. When shoots are about 3 - 5 inches tall, you can move them into a regular-temperature room in front of a bright, sunny window.  
10. Once flower buds come on, move the pot back to indirect light to prolong the blooms.
11. Generally speaking, once the blooms have died off, the pot of bulbs can be thrown away, as it is not likely that they will ever bloom again.

As mentioned in another article, when planted in the ground, the bulbs will last for year and continue to bloom year after year.  Forcing depletes the energy in the bulb, which is why they should be disposed of when finished blooming.  However, you can always try to get them to grow again by planting them outside.  You never know--it might work.  Planting instructions for previously forced bulbs is coming up.

Click HERE to get your free Printable Checklist!

Forced Bulbs Galore

One thing that can occur when forcing hyacinths is that they may not have an elongated flower stem and the bloom may "stick" in the clasp of the leaves.  This is easily overcome by placing the pot in the dark for a few days or covering the pot with a paper cone to "draw" the flower out of the bulb.

Forced Hyacinths

Paperwhites at Night

Although paperwhites will only bloom once, it is possible that some other bulbs will bloom again, if planted outside.  To give this a try, once the bulb blooms and the flower dies back, start watering the remaining foliage a little more frequently and add some bulb fertilizer. When the foliage yellows, cut it back and remove the bulbs.  You can now plant them outdoors in your garden.  However, it may take several years before the bulbs are able to build up enough energy to bloom again.

As I mentioned previously, my brother and I shared a house together for a few years before I moved to Texas.  At this house, there was a flower bed next to the driveway by the back door.  There wasn't much "good" soil in it and, when we moved in, nothing but weeds were growing there.  I wanted to try and pretty it up a bit, so every summer, I would plant some zinnias, cosmos, geraniums, little shrubs -- anything to make it look better than a gravel patch, which is basically what it was.

The third spring we lived there, I was just floored when two "magic" tulips appeared!  One was yellow and the other was red.  They just popped up.  They weren't really near each other; the yellow one was in the middle of one end and the red one was along the driveway edge in about the center of the bed.

As I said, this was our third spring there.  Prior to us living there, the landlord's twenty-something son had lived there for four or five years.  I'm relatively sure he didn't plant any tulips.  Before him, the landlord and his family had lived there.  So, it had been about eight years since anyone who may have planted the bulbs would have lived there.  Who knows?  Maybe someone had forced the bulbs, planted them out and then left them for dead when they didn't come up the following year.

The yellow one only came up that once as far as I know, but the red one came up every year after that.  I took care of that little tulip like it was made of diamonds!  However it survived, my brother, who lived in the house several years longer than I did, said it came up every year he was there.  As far as he knows, it still comes up every spring!

Forced Amaryllis

Forced Amaryllis on Cart

Forced Amaryllis Varieties

The amaryllis is really the only bulb that you can count on to bloom more than once.  Follow this slightly different set of instructions for growing amaryllis if you plan to relocate them to your garden after forcing.

1. Place the amaryllis bulb in light rich soil in a pot only 1 or 2 inches larger (wider and deeper) than the bulb itself.  The upper half of the bulb should be exposed above the soil.
2. Water thoroughly, then let the soil become quite dry.  Only after the soil dries out should you water it again.
3. Once the flower stalk appears, it can be watered more frequently, but only keep the soil damp to moist--not wet.
4. After it blooms, cut the flowers off to prevent seed formation.
5. Place the pot in the brightest location possible inside until it is warm enough outside to sink the pot in the garden soil.
6. When outdoor temperatures have warmed up somewhat, you should move the pot outside and sink it in the ground, first in a location where it will receive only dappled sunlight for the first two weeks.
7. After this, it should be ready to move it into a brighter location where it has full sun for at least 5 to 6 hours a day.
8. Fertilize your sunken pot with a balanced houseplant fertilizer at regular intervals to allow the bulb to build up the nutrients and energy needed for blooming the following year.
9. Bring the pot inside again in the fall before the first frost.
10. Allow the pot to rest in a dark location.  Withhold all water so that the remaining leaves can dry out completely.  This will take about 8 weeks, or until new growth appears.
11. The bulb may now need to be moved to a larger pot.  If the new pot is large enough, remove the top two inches of soil and refill with fresh potting soil.
12. The bulb is now ready for forcing again.  You should be able to repeat this same cycle for many years to come with the same original amaryllis bulb.

Click HERE to get your free Amaryllis Bulb Checklist!

Forcing Hyacinths without Soil

Most bulbs can also be forced without soil--only in water.  This is also known as growing "hydroponically".  To do this, follow the same chill-time requirements as with soil-forcing.  Then place the bulbs in a shallow bowl with pebbles in the bottom to keep the bulbs in place and to prevent them from sinking too deeply into the water.  Only allow water to cover the bottom quarter to third of the bulb.  For best results, the bulb should be barely touching the surface of the water, but it should always be in contact with it.  With this method of forcing, it will usually take about four weeks for blooms to show after you have "planted" them.

Forced Bulbs 1

If you have the room, start a new pot of bulbs every week or two and you will have constant blooms all spring long until the bulbs you planted in your garden are ready to bloom themselves!

Forced Bulbs 3

There you have it--everything you need to know to force blooms indoors this winter!  Have fun and enjoy!  Drop me an email or a comment to tell me about your own experiences with forcing bulbs!  Happy growing!

Peace and Love Always,

Forced Bulbs 4

Sources:

"Forcing Bulbs For Indoor Beauty In Winter". Extension.umn.edu. N. p., 2016. Web. 25 Oct. 2016.

"Forcing Spring Bulbs". Better Homes and Gardens. N. p., 2016. Web. 25 Oct. 2016.

"Growing Bulbs Indoors, Forcing Bulbs, Forcing, Indoor Forcing, Amaryllis, Paperwhites: Gardener's Supply". Gardeners Supply. N. p., 2016. Web. 25 Oct. 2016.

Photo Credits:

Forced Bulbs 2:  Photo Credit:  https://laidbackgardener.wordpress.com/2015/11/06/forcing-bulbs-without-twisting-arms/

Potted Bulbs:  Photo Credit:  http://www.rodalesorganiclife.com/garden/bulb-planting

Different Flower Bulbs:  Photo Credit:  https://www.lovethegarden.com/advice/gardening/flowers-shrubs/planting-bulbs-corms-tubers

Bulbs in Refrigerator:  http://www.gardenersworld.com/plants/plant-inspiration/nine-spring-bulbs-to-force-in-autumn/

Kitchen Hyacinth Huddle: Photo Credit:  http://pallensmith.com/2015/12/14/how-to-grow-hyacinths-indoors/

Paperwhites:   Photo credit: Berkeley Blue via Visualhunt.com / CC BY-NC-SA

Amaryllis:   Photo credit: douneika via Visualhunt.com / CC BY-NC-SA

Crocus:   Photo via Visual Hunt

Hyacinth Bulb Mix:  Photo Credit:  http://www.ufseeds.com/Color-Mix-Hyacinth-Bulbs.item

Muscari (Grape Hyacinth):   Photo via VisualHunt

Mini-daffodils:   Photo credit: CharlesFred via Visual hunt / CC BY-NC-SA

Standard Daffodils:   Photo credit: KatieTT via Visualhunt / CC BY-NC-SA

Tulips:  Photo Credit:  http://countrystore.net/fall-bulbs-spring-flowers/

Ready for the Fridge:  Photo Credit:  http://archive.feedblitz.com/860429/~4529634

Bountiful bulbs:  Photo Credit:  https://www.thisoldhouse.com/ideas/sandwich-bulbs-six-weeks-blooms

Cross Section--Bulb Pot Growing:  Photo Credit: http://www.101plants.com/content/container-gardening-lasagna-planting

Watering Can:   Photo credit: aldenchadwick via Visual hunt / CC BY

Windowsill Flower Pots:  Photo Credit:  http://pinkandgreenmama.blogspot.com/2013/04/spring-windowsill-garden-for-children.html#.WBPntC0rKUk

Spent Bulbs:  Photo Credit:  http://www.landspro.com/forums/showthread.php?1425-Gloxinia-Hey!-Don-t-THROW-it-AWAY!-It-s-Probably-Not-DEAD!

Forced Bulbs Galore:  Photo Credit:  http://www.recorder.com/The-theory-behind-forcing-bulbs-5223125

Forced Hyacinths:  Photo Credit:  http://www.theartisanshoppe.com/2014/12/30/pre-chilled-white-hyacinth-bulb-and-glass-vase-for-forcing-hyacinths/

Paperwhites at Night:  Photo Credit:   Phipps Conservatory by Clio1789 via Attribution Engine. Licensed under CC BY-NC-ND

Forced Amaryllis 1:  Photo Credit: http://www.livinggardens.com/amaryllis-forcing-vase#.WBEADi0rKUk

Forced Amaryllis on Cart:  Photo Credit:  http://www.whiteflowerfarm.com/how-to-grow-amaryllis-bulbs

Forced Amaryllis Varieties:  Photo Credit:  http://www.whiteflowerfarm.com/how-to-grow-amaryllis-bulbs?mobile=1

Amaryllis Bulb in Pot:  Photo Credit:  http://www.gardeners.com/how-to/pot-amaryllis-bulb/7258.html

Amaryllis Pots Outside:  Photo Credit:  https://cosmosandcleome.wordpress.com/2013/07/19/foliage-follow-up-july-2013/

Amaryllis Foliage in Garden:  Photo Credit:  http://www.sunnyvalegarden.com/flowers/amaryllis-belladonna-pink-lady/

Resting Amaryllis Bulb 2:  Photo Credit:   http://houseplantguru.blogspot.com/2011_10_01_archive.html

Amaryllis Bunch:  Photo Credit:  https://www.bakker.com/en-gb/p/amaryllis-mix-M45812

Forcing Hyacinths:  http://www.dutchgrown.com/blog/indoor-forcing-hyacinths

Forced Bulbs 1:  Photo Credit:  http://www.flowerbulbcrazy.com/forcing-flower-bulbs/

Forced Bulbs 3:  Photo Credit:  http://www.bhg.com/gardening/flowers/bulbs/forcing-spring-bulbs/

Forced Bulbs 4:  Photo Credit:  http://judyscottagegarden.blogspot.com/p/container.html?m=1