Find out how to plant flower bulbs. Learn about the basic rules for planting bulbs and also get tips and design considerations for specific plants.
LESLIE: Well, nothing signals the start of spring better than those fresh blooms, like daffodils and tulips in full color. But if you want to enjoy those beautiful, spring blooms, you kind of need to get planting right now.
And Roger, the secret to successful blooms all starts with the timing, right?
ROGER: Absolutely. But to be a gardener, you have to have an absolute leap of faith because when you’re talking about bulbs, you’re talking about putting something in the ground over the winter and it’s going to bloom in the spring.
TOM: It just doesn’t make sense.
ROGER: Doesn’t at all, expect when you figure out where these bulbs come from and the mountains where they freeze for the winter and then bloom. This is the only way they can survive.
LESLIE: So really, with all blooms, the secret is put them in in the fall, with all bulbs. There’s really no other opportunity to plant later in the season and have them come up, say, in the summertime or …?
ROGER: There’s two different categories of bulbs. The spring flowering bulbs all have to be planted in the fall. Summer flowering bulbs like dahlias and things like that are planted in the spring.
LESLIE: It’s a great mystery.
ROGER: So confusing, isn’t it?
LESLIE: It really is.
TOM: Yeah, it really is.
Now, what are some basic rules that sort of apply to all bulbs? Like starting with the type of soil that they like.
ROGER: Well, bulbs hate wet soil and some of them won’t do well in shady areas.
ROGER: They’ll bloom the first year but they won’t reset for a second year if it’s too shady. The biggest mistake people make is not planting bulbs deep enough.
LESLIE: Well, because they’re a squirrel’s favorite food, right?
ROGER: No, they’re not. That’s – no.
LESLIE: Really? Then what are they doing in my garden all the time?
ROGER: If you plant a bulb with a bone meal, bones are something that squirrels eat naturally. They go after that particular product. But that’s planted underneath the bulb. They’ll actually dig, throw the bulb out of the way and eat the bone meal out of the soil.
TOM: Oh, so it’s not the bulb, it’s the bone meal they’re looking for.
ROGER: Right, right.
ROGER: So that’s why we use a product called “superphosphate,” which encourages root growth in the bulbs but it’s not attractive to rodents.
LESLIE: And what’s the trick? I mean we had wonderful success with tulips one season – there was a bajillion of them – and then the following year, maybe like a third.
ROGER: Yeah. Wow, that’s the thing with tulips is especially if they’re planted shallow, they’ll only bloom one year and they won’t follow that up. They won’t keep reblooming or – naturalizing is the term we like to use.
So what – the trick with tulips, plant them deep and every year, supplement that bed with the same-color tulips you put in before.
LESLIE: OK. And how deep? Am I going down a foot or just a couple inches?
ROGER: Basic math formula is two-and-a-half times the size of the bulb.
ROGER: That’s how deep you dig the hole. So in most cases, for a tulip, you’re going to be at 5 or 6 inches.
TOM: Now, what about daffodils? Those are sort of the workhorses of the spring flowers.
ROGER: Daffodils are my favorite. They seem to never fail. They thrive, they naturalize, they come back year after year. And for the money, I think they’re your best bang for the buck.
TOM: How do you plan a garden  that’s going to be all bulbs? Do you bunch the colors together? Do you mix them up? Are there considerations about height?
ROGER: Absolutely. And more important than all is sequence, is when they’re going to bloom.
ROGER: Because you don’t want a tall one blooming in front and have a short one behind it and not be able to see it. It’s all about sequence and massing of plant material. I love to mass bulbs: a whole bunch of them planted together.
LESLIE: Now, so many mail-order catalogs flood our mailbox at home and you see these beautiful blooms and you’re like, “Oh, I’m going to order these bulbs.” Is it better to get them from a catalog or head to my local home center and really see and touch?
ROGER: I do both. I love to support the local garden centers but sometimes I can’t get what I need at the garden center, so I have to reach out and get it someplace out. The key to remember is that when you buy bulbs, they’re all bought by size. So you have to look and compare size. If you’re going to buy a 12-centimeter bulb or an 18-centimeter bulb, there’s a different in price. And the bigger the bulb, the bigger the flower or the more flowers it’ll have.
LESLIE: The bigger the height or …?
ROGER: No. Just the bigger the flower: the bigger the plant itself.
ROGER: Within each species of plant, you can buy little, short ones, medium and tall. And then the sequence goes with that: early, medium and late.
LESLIE: Oh, goodness.
ROGER: So one thing that you can do is you can always buy bulbs in a naturalized mix, meaning that when you buy it, there’s three or four different types in there. So when you plant it out, they sequence themselves; you don’t have to do the math and figure it out.
LESLIE: Mm-hmm. But do you need to physically look at the size of the bulb and sort them based on the size of the bulb, so that you can see everything in the bed?
ROGER: No, no. When you buy a bulb, you’re going to know what height it’s going to be. And these mixtures, you just throw the whole mixture out and they’ll all pop up at different types and they’ll all be about the same height.
LESLIE: Very nice.
TOM: So buy the mixture and they kind of do the work for you.
TOM: Great advice. Roger Cook from TV’s This Old House, thanks so much for stopping by The Money Pit.
And for more tips, including a video of how to plant bulbs, you can visit ThisOldHouse.com.
LESLIE: And remember, you can watch Roger and the entire This Old House team on This Old House and Ask This Old House on your local PBS station.
TOM: Thanks, Roger.
ROGER: Oh, you’re welcome.
TOM: And This Old House and Ask This Old House are brought to you by The Home Depot. Home Depot, more savings, more doing.