Thousands flock to the Skagit Valley each April during their annual tulip festival to see the breathtaking rows and rows of colorful tulips and other flowers.
As you might imagine, playing host to the world means keeping a keen eye on the weather for all the incoming guests, while at the same time crossing fingers that Mother Nature provides the need sun and rain to make the tulips their very best.
I always wondered if the weather in March and April affected how the tulips would grow each year -- if it's sunny and warm for too long or if it rains for four weeks straight, can it damage the bulbs or, worse yet, wipe out the show? Can you gauge how well and how long the tulips will remain in bloom based on the weather leading up to and during the festival?
It turns out, tulips are a pretty hearty bunch and the general climate of the Skagit Valley ensures there will be a show each year, no matter what crazy weather March dishes up. But Brent Roozen, with Roozengaarde Flowers & Bulbs says weather can affect when the show begins and how long it will last.
"If the weather is on the warm side of things than the tulips can bloom in late March," Roozen said. "And if the weather is on the very cool side for a prolonged period of time, then the tulips will hold for a while before coloring/blooming."
Roozen recounted a few years ago when his farm had both extremes -- one year they bloomed on March 20-23; the next year a chilly spring held them in the ground until April 15-18. But their month-long festival is usually perfectly timed to the tulips' blooming.
"The tulips want to bloom in April," Roozen said. "So even if the weather is cool for a long period, a short period of sun/warm weather will help even things out very quickly."
He said the longer the tulips wait to bloom, the less sunshine and warmth they need to actually bloom.
But some weather patterns have to be better than others, right? So I ran through some weather scenarios with Roozen to find out which ones pose the greatest benefits and threats.
We're all well-known for our rain, but can it rain too much for tulips?
"Too much rain or prolonged periods of extremely cold temperatures are the worst case scenario for tulips," Roozen said. "Honestly though, either of these extremes happens just about hardly ever in Washington." As I wrote earlier in the blog, the Skagit Valley's climate is perfect for tulip growth and is well protected from the weather extremes that would damage tulips.
Roozen says even "too much rain" is relative and depends heavily on the timing of the rain and the condition of the field.
"Very rarely do we have losses because of too much moisture, but it happens from time to time if a low lying area of a saturated field gets a prolonged period of rain," Roozen said. "We actually plant bulbs (in the fields) on the surface of the soil and mound up the rows over the top of them. This helps protect the bulbs a little more in saturated conditions."
On the other hand, that does make them a little more exposed to freezing temperatures because they are not insulated quite as well.
Which begs the next question:
How cold is too cold for the tulips?
Roozen says while winters are wet here, we get limited freezing, and tulips really aren't affected by a freeze until low temperatures drop into the teens or low 20s for a few days.
Those harsh conditions are pretty rare in the Skagit Valley but even on the rare occasion they occur, it's not necessarily a death sentence for the tulips.
"Too cold depends on how advanced the development of the flower is," Roozen said. "The later the freeze, the more damaging it can be. A temperature of 10 degrees in March would be a lot more dangerous to the flowers than the same temperature in December."
He says when tulips begin to grow, it is not uncommon to get some frigid temperatures.
"But these will typically only result in the freezing in the tips of the leaves. Like humans, the extremities on tulips are at risk first," he said. "However, 99.9 percent of people would not even notice a little frostbite to the tips of the leaves. It almost looks natural. The biggest risk is having a freeze when the buds have formed and are growing. How often does this happen? Not that I can remember… but I am still kind of young."
Roozen says tulips and other flowers are much smarter than we give them credit for.
"Seriously, they know the weather better than we do since they are responding to it entirely. Two or three years ago we had a prolonged freeze with temperatures in the teens for a few days. This happened as we were picking daffodils so it was pretty late in the year. I only saw a little damage to the earliest blooming daffodils. Nothing else was really affected and again, 99.9 percent of people would not even notice the damage to the daffodils. They just didn’t look perfect to me."
Freezing temperatures: Bad. But have I heard that snow can a good thing?
Roozen said I heard correctly.
"Snow is usually a good thing," Roozen said. "When we get a few inches of snow and the temperature drops, that layer of snow provides a little bit of insulation from the cold air."
Growing bulbs in containers is a different story. For those with wine barrel/container plantings Roozen advises them to be aware of temperatures in the teens because their bulbs are more exposed. The soil in containers will also dry out more quickly which can dehydrate the bulbs and freeze too.
What's the worst Mother Nature can dish out?
Roozen said hail is the worst thing for tulips because it can cause damage by spotting.
"Not sure most would notice these weather spots but I certainly would," Roozen said. "And you would too if I put two tulips right next to each other."
And a super rainy day that has strong winds isn't the best either.
"It's not so bad for the fields but we’d prefer to avoid it in the display garden as we have some unique Double Tulip varieties and daffodils that can be weighted down by a lot of rain mixed with wind," Roozen said.
Over the long term, a wet spring followed by a hot June can cause the bulbs to become infected and rot before and during harvest.
So, then sunshine has to be good, right?
A stretch of sunny and 65-70 degree days in April is sure to be cherished by many, but Roozen says the only downside to a sunny streak is that it can accelerate the growing process to where the tulips simply won't last as long.
"Cool temperatures act as a sort of natural refrigerator," Roozen said.
On the the other hand sunshine will bring the crowds out so that more people might actually see the tulips over a short period than an extended cool, rainy period that prolongs the tulips but keeps the crowds down.
So what's the perfect weather scenario that Mother Nature could order up?
"The perfect weather scenario is one that I am afraid never exists!" Roozen joked. "But it would go something like this: Cool weather with no chance of rain during the weekdays and a little warmer weather with the sun shining on the weekends."
He says a little rain here and there isn't a bad thing.
"It gives the diehards a chance to view and photo the tulips without any crowds," he said. "Cool weather helps the blooms last a little longer and sunshine motivates the people to come on out to see the tulips. So any combination of those is the perfect scenario, but the weekend crowd has a tendency to be a little more of the fair weather type."
But he says if you're willing to brave a little cold or sprinkles, you'll have the benefit of viewing the tulips with almost no traffic and no crowds.
"We want everyone who comes up to have an exceptional experience that they will both enjoy and remember. The weather plays a part in that," Roozen said. "So I've got my fingers crossed for a pleasant April."