Is My Bulb a Perennial Or An Annual?
This is a question we get asked a lot: Is my bulb a perennial or an annual? And we’re not trying to be coy here, but the answer is “it depends.” Bulbs are a little different than other types of plants that neatly fit into the perennial or annual categories, and this blog post will explain how.
And if you’re hearing that little voice inside your head that says, “What does it matter? If it comes back, it comes back!” then we want you to take a hot minute. If your bulb in question is a perennial and you’re thinking it might be an annual, we don’t want you pulling that bulb out thinking it’s done! The very thought is horrifying, wouldn’t you agree?
Perennial vs. Annual Bulbs
Let’s first be sure we’re all speaking the same language. Perennial bulbs are those that come back every year, and often with more blooms than it sported the year before. Annual bulbs, on the other hand, complete their life cycle in one growing season, so you have to plant new bulbs every year.
Now, the reason we said “it depends” in the opening paragraph is that with some bulbs (eyeballs on you, tulips), they will come back year after year if you live, say, in a town in Northern Iran. And even if you live in the United States, if you garden in a cooler climate then your bulbs might be treated differently than if you live in San Antonio, Texas. So, bulbs that are perennials in our garden might not be perennials in yours.
Many spring-blooming bulbs need to go through what we call a “winter chilling” period in order to complete their life cycle, and this means you’ll need temps of 40 degrees or colder for at least 12 weeks. If your climate is warmer than that, you’ll need to pre-chill your bulbs in the fridge — and these bulbs should be treated as annuals.
Determining which bulbs to plant
So, before we go any further, you’ll need to know these things:
- What bulbs are currently in your garden
- Which bulbs you’d like to add to your garden
- What your growing zone is
- What the bulbs in your garden need in order to come back every year
You may find, after gathering this information, that you want to fine-tune which bulbs you grow so they align with the growing conditions in your area. Or, if that doesn’t matter as much and you’re perfectly happy doing a little extra work, then we heartily support you.
Bulbs that are perennial under ideal growing conditions
There are exceptions to all of these. Of course there are. Bulbs are special. For example, dahlias are not cold hardy in most areas, but you don’t want to consider them annuals and simply throw them out. Diehard dahlia lovers dig them up, store them for the winter, and replant in the spring. Why? Because dahlia tubers are expensive, but an initial $15 tuber will multiply and give you scores more over time. Well worth the extra labor, in our opinion! P.S. Italian ranunculus behave much the same way that dahlias do.
And tulips are always an exception to any rule. In general, they are perennial but only under the right growing conditions. If they come back for you, they may only do so for a couple years before they decline. Species tulips are more dependably perennial.
Most bulbs are perennial somewhere, and if your garden is not that somewhere that, say, tulips really like, then you have a few choices: 1) Don’t plant tulips. The horror. 2) Plant them new every year. 3) Plant them and experiment to see how many seasons you can get out of them. One of our team members lives in Austin, Texas, and desperately wants to grow dahlias. Can she? Yes. Will she need to do a little extra work? Yes. Will she? Time will tell!
- Jenny Peterson