Our Tulip Forcing Journey

As a Canadian grower it used to feel like summer was 3 short months of blooms for enjoying. I remember when Floret Flower launched their book called "A year in Flowers" and I remember thinking how? Floret is located in Washington and I couldn't imagine their growing zone being that much more superior for growing flowers than ours. Located here, just south of Calgary, Alberta, we are a zone 3B (I guessed they were a 5 and still have not researched it) but occasionally our winters can be categorized as a zone 4. I am always willing to take the chance on a zone 4 plant just incase it works out. But I still couldn't fathom such a length of growing period until I stumbled on forcing.

Coming into forcing tulips was almost forced on me! Having just started up my online shop last year for my Fall 2025 sale, I made the mistake of majorly over-investing in tulips. This was a learning curve for me for knowing how many I could sell and although I did pre-purchase some water forcing trays, the number of unsold blooms I was left with was staggering and in the thousands. Welcome to my tulip forcing journey.

Mapping it out

If you are new to tulip forcing you may not know that some tulips are good for forcing and some are not. Most of the tulips you can force all have a suggested number of weeks they require for their 'cold treatment' and with as many bulbs as I had, I couldn't very well sell them all if they all bloomed at the same time in May from planting them in the ground. So I got to work making a schedule.

Timing: Cold period > Greenhouse Period > Blooming Period

Example: Cold treatment 16 weeks > Greenhouse 22 days > Blooming

The problem is that most varieties have different cold treatment times and greenhouse days.

I found that the best way to do it was to work backwards from the blooming week! An example excerpt from my schedule looked something like this.

Blooming Week: February 8

Varietys:

Apricot Pride (16 weeks cold, 21 days greenhouse growing) > Greenhouse Jan 18, Plant Sept 28

Silk Road (14 weeks cold, 18 days greenhouse growing) > Greenhouse Jan 18, Plant Oct 12

Angelique (16 weeks cold, 22 days greenhouse growing) > Greenhouse Jan 18, Plant Sept 28

I worked from 'Blooming week' first. I tried to match up bloom colours so that different varieties would bloom during the same week and then counted back the greenhouse days (usually 3 weeks prior) and then count backwards for each varieties cold period. Some greenhouse days varied up to 6 days but to simplify I rounded all greenhouse days to 3 weeks. Tricks like putting the tulips in the fridge with bulbs still attached and drinking can help them to keep longer while the other varieties bloomed. My list suddenly was more simplified with instructions for what to plant each week.

I made colour coordinated labels that each had a different coloured dot to signify which week I'd bring them into the greenhouse.

After that, all that was left was planting! I would pre-soak my soil, fill the pots, pop them in and cover.

With some varieties I was able to put them directly into the fridge, still in the bag, to use a method called Water Forcing. Pictured below is my first batch I pulled out and lined up in my forcing tray. *A special note on these is to not allow the bulbs to touch the water as it can quickly result in rotting. The bulbs sit above the water and the roots will reach down to drink it.

A few problems I had to trouble shoot:

Watering - For the first 2 full months, I would check the soil by sticking my finger an inch or 2 into each pot and if I felt any cold I would know it still contained moisture. The bulbs can rot very easily if there is too much moisture and without roots, they have nothing to soak up the moisture with. After this I did have to spray them each with the hose and I tried to do less water than more. Some of them still ended up sunken looking and completely soaked but the fallout of this is unknown until I can see if they grow.

Temperature - Thankfully I have a large heater in my garage. We had set it for about 5 degrees for the whole of winter which worked really well. Even with our cold-snaps we didn't ever have a freezing temperature in the gargae. The bulbs in pots are not supposed to freeze. Honestly though, I'm not really sure why since they definitely do that in the garden.

*An important note is once the bulbs get to a temperature of 9 degrees, they will begin to grow! Unfortunately with this very warm spell in February, I have some tulips that are not due to go indoors until March and April that have already began poking through. I'm crossing my fingers I can cool them more and stop the growth but I won't know for a while if this works or not and may result in some spent tulips!

Invisible Emissions - Apparently tulips bulbs are very susceptible to multiple types of gases including the ripening gas created from apples and various other fruits. I had to remind myself time and again while I potted each week not to allow them to sit near any fruit on the counter. Also, I do park in the same garage that the cold pots are resting in. I have had to be cognizant that I open the garage before I start my vehicle and leave and had to remind all members who use the garage not to start things like gas generators. (A very real occurrence this winter.)

Unknown Cold Periods - I had a tulip called "Silk Road" that I could not find any forcing instructions for, therefor I just had to guess at the cold week period. Funny enough, this one was among my 4th or 5th week that was to be brought indoors and then it was the first pot in my garage that started to sprout up. At 14 weeks along (I had schedules it for 16 weeks) I brought the first 2 pots in since they so eagerly wanted to grow and were already 4" tall. And it was a success! Feeling up the length of the stem as it grows, you can feel the bump that is a bloom coming up. All of these bloomed beautifully thankfully, but others that are due to come in also show no signs of growth and as you may now be aware, multiple problems could have occurred.

Experimentation - For the sake of learning I decided to experiment with some of the bulbs and change up the cold timing. Some of the online guides I found were listing tulips on my list with different cold week periods than were specified on my forcing work-sheet from my supplier. For example: Mystic Van Eijk had a forcing period of 15 weeks on my guide. Since it is an early single I decided to try out a few shorter lengths and did schedule my first tulip pot to be brought in at 13 weeks. It was a complete success! After all, it's not like the bulbs can tell time.

Greenhouse days - Usually greenhouse days are scheduled between 20-25 days, my first Mystic Van Eijk pot bloomed after just 12. I have another pot blooming now at 15 weeks cold period with petals completely missing from one side - I am taking that as a note that the shorter cold period was better for this variety and am making notes for every variety I have forced this year.

If you are looking to try your hand at forcing, don't be deterred by online suggestions that this is only a sport for an expert or that it can only be managed using "paperwhites". I have ample evidence that this is not true! See below one of my favourite beauties from forcing this year, Silk Road, a bloom with no sited instructions that I could find anywhere that was a complete success anyhow.