Forcing Flower Bulbs

There are so many people who really miss out on Spring blooming bulbs! (Those in zone 8 or warmer).  Then there are people like me who long for winter to be over and want flowers all the time.  So, forcing bulbs is a great option to get those blooms!

Typically, growing flower bulbs is almost fool proof, but forcing bulbs takes a little more time and attention.  “Forcing” bulbs is the term used for mimicking what normally happens to bulbs when planted outdoors.  It is a process that stimulates bulbs to bloom out of season.

The most common and easiest bulbs to force are:  paper-white narcissus, amaryllis, muscari, and hyacinths.  Daffodils and tulips are not too difficult either, but choose shorter varieties for best show.  The best tulips for indoor forcing:  Triumph Tulips, Single Early Tulips, Darwin Hybrid Tulips.  Spring flowering bulbs usually require about 12-20 weeks at temperatures between 41-48°F in order to produce a good root system for the best blooms.

Name of bulb                         Weeks of cold                    Weeks to bloom

AmaryllisNone6 to 10
Chionodoxa152 to 3
Crocus152 to 3
Hyacinths11 to 142 to 3
Iris152 to 3
Muscari13 to 152 to 3
Narcissus15 to 172 to 3
Paper-whitesNone3 to 5
Scilla12 to 152 to 3
Tulip15 to 202 to 3

Pot your bulbs right away if you have an appropriate location immediately available, such as a refrigerator, a root cellar or cool basement, or outdoors if temps are below 48°F.  When storing pots outdoors for cold period be sure that if temps drop below 30°F that you cover them with some type of insulation.  If you can’t plant them immediately, bare bulbs can be stored in a mesh bag or paper bag with holes that permit ventilation for several weeks in refrigerator prior to potting without damage.  Note: Do not store them in same drawer as fruit.

Use clean pots with drainage holes and plain potting soil. Make sure you allow for 2 inches of soil below the bulb and select a pot large enough to allow the top of the bulb to be even with the rim when placed on the soil. The bulbs should be touching each other for the best look when blooming.  Then water them well in order to settle the soil.

The bulbs will flower anywhere from 2-5 weeks after they have been brought into warmer temperatures.   If you have a set time when you want them to bloom, make sure you add flowering period to the rooting/cold period for the total number of weeks to wait.  Amaryllis and Paper-whites do not need this cold period.

These next steps would be ideal for the best and most perfect blooms Move your pots to an indoor area with indirect sunlight and temperatures about 60°F for a week or two.  When the shoots are 4-6 inches tall, move the pots to a bright, sunny window to stimulate blooming. A temperature of about 68°F and direct sunlight would be ideal.  When you see the color on the buds, return the plants to indirect sunlight to make the blossoms last. Keep the soil moist at all times.

After blooming, hardy bulbs such as hyacinths and tulips cannot be forced again and should be discarded. Or they can be planted outdoors where they may rebloom within a year or two.

Amaryllis bulbs will bloom again and again, provided they are properly cared for. After the bulb finishes blooming, cut off the flower stalk close to the base. Keep the plant moist and add house plant fertilizer.   Stop watering in August, and allow the plant to dry out completely in the sun. In early fall, remove and clean the bulbs of old scales and dead foliage. Roots should be fleshy and not damaged.  You can re-pot when you are ready to restart the process.

Maybe you will want to give this a try now?  I especially enjoy forcing Hyacinths for indoor enjoyment because of there sweet fragrance!  I hope you found this helpful and easy to understand.

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29 Responses to Forcing Flower Bulbs

  1. Elizabeth says:

    I have a bunch of tulip bulbs and planted them in pots last year and they all sprouted and I was looking forward to the flowers but they never actually flowered. Someone told me it takes a year or 2 for the flowers to actually come out, I don’t know how true that is. I live in an apt and had the pots on the window sill. I dug up the bulbs after the green leaves all died and I was going to attempt to plant them again this year and hopefully get them to flower. What are your thoughts?? I wish I had a a garden. I’m working with what I have.

    Thank you, any advice would be helpful.


    • Gabrielle says:

      What a disappointment! It sounds like they did not get enough cold temps before sprouting or they never had a chance to rejuvenate themselves after blooming the previous year.
      My questions for you: Had you just bought the tulips last year? Did you follow the steps for forcing bulbs?
      If the bulbs are still firm and healthy, I would plant them to see if they will flower. If they had enough light and water last year to rejuvenate the bulb, they may just bloom this year.
      But also know, forced bulbs are generally no longer viable after blooming. Unless they are kept in the ground- they just do not keep year after year.

      I wish you the best! Let me know if you get any flowers!

  2. Kako says:

    Hello enjoyed watching your video. I’ve recently purchase Gladiolous bulbs and I’m wondering if it’s safe to plant in pots vice garden. I currently live in Florida so the sunshine will be no problem. I’m kind of reluctant however I’m willing to try?


    • Gabrielle says:

      Sure you can grow Glads in pots. Since you are in Florida, you can plant in various pots at a few week intervals to get continuous blooms of glads over a longer stretch of time. Just don’t forget to water more often!

  3. Val says:

    what a great blog, I am going to try this with some tulips sitting them on the cellar stairs towards the top by the door, this is pretty cold, yet not freezing. My only question is, after initial planting and watering, should I put a smidge of water on them now and then as if they were outside, or will they rot if you give them any water at all? thanks very much, Val

    • Gabrielle says:

      Sounds like a good option to try. Water when planting and then leave it. Just make sure to give some water right when it starts to warm up!

  4. Sharon says:

    Thanks for the simple to follow instructions! I’m planning to force narcissus and muscari bulbs together in small planters for my late April wedding and I have a few questions.

    They have different amounts of time listed for cold storage, is there a way I can plant them together and have them bloom at the same time?

    If I follow your directions for timing and temperatures, how closely can we predict the date they will bloom?

    Thanks – Sharon

    • Gabrielle says:

      Im glad you found it helpful. If your plan is to have them in same containers, I would chill for 15-16 weeks. Flowering time can take 2-3 weeks after you take the out of colder area. You want them to look great on one day. (depending a lot on temperatures. and too much heat could make them bloom and wilty fast.) That is where your gamble will be. Because it is such a special occasion- I would make a back up plan.
      I wish you the best!

  5. Esther says:

    I have some tulip bulbs (parrot) from Holland. My zone is 4 and it is snow outside with very low temp, so the ground is frozen. I do not want to wait because some bulbs have rotted. What should I do? store bulbs in garage or plant in pots and keep them in the frig? Also I have never planted anything in my life and the bulbs were a gift from my daughter.

    • Gabrielle says:

      You will need to force them according to my blog post. Pot them up asap and provide the cold temps. Otherwise they will continue to rot and just be garbage. If the bulbs you still have are firm, You should be able to get them to bloom!

  6. Becky says:

    I have some Brecks tulip bulbs and planted them in a bad spot (too many pines around) They bloomed the first year, some the second and now nothing. Is there anything I can do to save them and get them blooming again. I so love the tulips and would love to have them again. Thank you!

  7. Bert says:

    I have received newly ordered tulips and daffodil bulbs from Brecks. I live in zone 4. I wish to plant in several hanging planters (24″ long x 5″ wide x 6″ deep) around my deck. When I ordered the bulbs, I had planned to plant this this fall/early winter. Knowing that the low temperatures here in Minnesota can stay below zero for a week or so at a time, is my plan set up to fail simply because of the relatively small containers that will freeze?

    • Gabrielle says:

      A few items to consider:
      Generally if you plant in planters, you need to act like you are actually one zone colder than you really are.
      Also, when dealing with fall bulbs, they actually grow/root in the cold temps. With that in mind, you would want to ensure a good layer of dirt between bulbs and side of planter. Bulbs like to get cold, but not frozen. So having up in the air and not on ground and somewhat insulated, would be a bad idea.
      If you use planters on the ground, somewhat insulated, you must also be sure of drainage holes.
      I hope this helps!

  8. Kim says:

    I live in zone 5/6. I am planning to try to force some tulips and maybe some other bulbs for an April wedding. If I plant them in pots it will be too cold for them outside so I was wondering if I could just plan to dig a hole in the ground for the pots and then attempt to dig the pots up up when I want to bring them inside. Do you think this would this work? Would the pots be able to drain as needed?
    Thank you!

  9. Carol Camilleri says:

    I recently read an article about planting bulbs in pots. I live in Michigan and want to try this with 2 huge urns. Will it work?? Also, I plant annuals in them in the summer and know you have to let the leaves turn brown to give energy back into the bulb. Can I dig them up and let them die back without leaving them in the urn? The leaves wont be brown until long after I want to refill my urn with annuals.

    • Gabrielle says:

      Great questions! First important point to note, being in Michigan, you must protect the bulbs from freezing. (When in ground over 4 inches they do not freeze like they could above ground in an urn. You would have to move planter to protected garage and maybe even add some wrapping around to insulate some.
      Secondly, if you dig up bulbs before the green has yellowed- then they will not die back naturally. You would be killing them. 🙁
      Another idea to help do what you want, come up with some type of planter that would fit inside Urn. That may work a little easier for winter and for being ready for annual. (like switching out an insert)
      Hope this helps!

  10. Chris says:

    Would burying my decorative plastic containers with tulip bulbs in my raised vegetable beds be sufficient for overwintering? I can line the hole in the bed with plastic so my containers don’t get too cold and so they won’t get as dirty. They would be buried up to the tops of the containers.

    • Gabrielle says:

      Good idea. Here are some details to keep in mind: when planting containers in raised beds, it is much the same as a container- make sure its a foot away from outside of box for more insulation. Make sure bottom of pot is not sealed in with plastic as drainage is still very important.
      Good luck!

  11. Becky says:

    Hi Gabrielle,
    I live in San Antonio, which is nearing south Texas. I just dug up some forgotten bulbs (tulips and daffodils) from this past spring, and now I’m not sure what to do. Should I put them in the refrigerator now (end of Oct) and then bring them out the beginning of January to plant outside? Or should I go ahead and just replant them right away? It almost doesn’t get cold enough here for them – or so I’ve been told – and that I should refrigerate them first before I try replanting them. Almost all of them bloomed this past spring, and I don’t want to lose them if I can help it.
    I’ve read your great blog and comments and I appreciate the work.

    • Gabrielle says:

      I am not sure if it got too hot for them this summer or not (drying them out). BUT if not, They definitely need to be refrigerated for many weeks. They need 15 weeks of cold (@36°). Keep them refrigerated as long as needed and then plant. (I assume you may not even have regular temperatures in February at 40° or less??) If you do, part of those 15 weeks may be planted outside.
      Good luck!

      • Becky says:

        Thank you! They are still beautiful and full of roots. I am putting them in the fridge right away. I appreciate your help.

  12. MA says:

    I would like to try to force some bulbs on my balcony in zone 5 with some makeshift protection. I don’t want to use a fridge and don’t have land. If I plant them deeply enough with soil around thm, put the pots next to the building for some minor warmth, would clear window insulation taped over them retain enough warmth to keep them between the necessary 32 to 40 degrees for the 15 or more weeks needed? At that time of year only indirect sun hits the balcony. Thanks for any thoughts.

    • Gabrielle says:

      Sounds like you have good ideas to try, and I cannot think of any better ideas for you. Just make sure you have watered them! But it sounds like you have a good chance at getting them to grow in spring!
      Good luck!

  13. William says:

    Hello–I want to order some pre-chilled bulbs which arrive 2nd day air. Could I keep some in fridge or other cold spot so I could bring them out little by little, or does the pre-chill process stop as soon as they come out of chilling from the supplier? Also is it possible to pre-chill bulbs for too long? Thanks for any insights you might have.

    • Gabrielle says:

      You can bring some out each week for continuous bloom times! Yes, the longer the bulbs are out of the soil, the higher the chances for them to dry out. Ideally, you want them planted asap and keep them chilled that way. Have fun!

  14. Summer says:

    I live in zone 6-7 but my question will only apply to indoor planting. I’ve purchased some Tulip bulbs last Autumn and left them in a cool closet all this time. My plan is to plant them in a pot and let them grow indoor. Will I have to put them in a refrigerator first before I plant them? It is 14-30 degrees outside right now. And…if I decide to them in the railing basket, when shall I do that? Thank you.

    • Gabrielle says:

      The bulbs are alive and can only be stored/ dormant for a period of time. If they seem firm after being out of soil since this summer(when they were harvested), you can try to chill them. Unfortunately, I believe they will dry out and die (if not already). Tulips need a minimum of 15 weeks of temps below 40°, in order to grow and bloom properly.

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