Lasagna Planting: Layer Bulbs into Your Pots for a Riot of Blooms
Updated: 17 minutes ago
Nothing says fall like sweater weather, a pumpkin stack and bulb planting.
Bulbs have become my favorite flowers to grow — and by bulbs, I'm talking 'bout the whole genre: bulbs, corms, tubers, rhizomes… if you want to get technical.
They come in all shapes and sizes. They look pretty gnarly and it’s tempting to doubt them, but they show up again and again, offering the most reliable — and beautiful — flowers I grow.
The fall-planted ones are my favorite — the daffodils, hyacinths, muscari, anemones and ranunculus. The latter two take the cake IMHO.
Note: I'm a backyard gardener in coastal NC — zone 8b. It's a mild climate where the ground rarely (if ever) freezes. If you live in a colder zone, where the ground does freeze, hold off on planting anemones and ranunculus until spring. Otherwise, the rest of the list (plus tulips, which sadly don't grow well here unless pre chilled) not only withstands very cold temps, but welcomes them.
OK, I pause my lovefest for bulbs to get to the nuts and bolts of my favorite way to grow them: lasagna planting.
What Is Lasagna Planting?
Lasagna planting is a gardening technique that layers bulbs — in ground, or in pots — to extend your spring flower display and to create a diversity of interest. Think: a living floral arrangement.
Newly planted bulbs are powered with everything they need to bloom and require little water or care, this makes for a low-maintenance grouping that plays well together. They are determined to bloom and the deeper planted varieties (like daffodils, tulips) will push their way through the upper layers.
Before You Plant: The Prep Work
Know Your Zone
What grows in your zone? First it's important to select material that works in your climate. Here’s a quick reference for my favorite bulbs to grow.
Choosing the Right Pot
Bulbs require different planting depths and herein lies the secret to lasagna planting.
Once you've selected bulbs that work in your zone, check to see what the greatest depth requirement is (see chart below). Your pot needs to be at least 4 inches deeper than that for root development. In terms of width, I wouldn't go smaller than 6" in diameter at the bottom of the pot. The larger the pot, the less maintenance it requires (more insulated from freezing temps and needs less water) and the more space you'll have to layer.
Drainage is the one thing I'd fuss over. Bulbs are generally forgiving, but don’t tolerate a wet bed — soggy soil is a sure way to rotten bulbs. So make sure your container drains well, and skip the old crocks-and-gravel-at-the-bottom trick. Counterintuitive as it sounds, it raises the water line inside the pot rather than letting it out. Skip the saucer too. Beyond that, water only when the first couple inches of soil feel dry to the touch and pull your pots under cover if you're in for a long stretch of rain.
When to Plant
Fall bulbs should be planted when soil temps are around 60 degrees, which is around the time of your first frost, when leaves start falling off trees. For me in Southeastern NC that's mid November. Regardless of the research-based recommendations, I've found that bulbs are pretty flexible. I've planted mine as early as October and up until January with good results.
Materials You Need
Clean pot (see size guidelines above)
Potting soil (NOT garden soil)
Pine Bark Soil Conditioner
Planting material: bulbs, annuals, seed - check out some of my favorite varieties here
Gloves
Hand trowel
Soil Scoop
Osmocote or a similar slow release fertilizer to feed plants in containers
How to Layer Bulbs in a Pot: The Recipe
Bulbs are generally planted 2 to 3 times their height deep, measured to the base of the bulb — so the bigger the bulb, the deeper it goes. That's the whole mechanic behind layering.
Work bottom to top:
Deepest layer
Your largest bulbs planted 5-6” deep like daffodils, hyacinths. Space them across the bottom (you can place them as close as eggs in a carton). Make sure you’ve filled the pot till the soil line is at the bulb’s recommended planting height. When working in large pots, I mix soil conditioner into my potting soil: 1 part soil conditioner to 2 parts potting soil.
After placing bulbs, cover with 2" of soil.
Middle layer
Mid-sized bulbs planted 3-4” deep like small-cupped and jonquilla daffodils, species tulips, muscari. Cover again.
Top layer
Your shallow corms planted 2” deep like anemones and ranunculus, tucked into the gaps between your cool-season plants, or covering the top of the pot.
Sort by the actual size of the bulb in your hand, not by what it is — a fat 'Ice Follies' daffodil belongs in the bottom layer, a small 'Baby Moon' in the middle.
And you don't have to plant 3 layers - 2 layers, or even 1 layer, interspersed with cool season plants from a nursery works, too. They key is to honor a bulb's preferred planting depth.
Two other placement rules to keep in mind: keep shorter stems toward the rim and taller ones toward the center so nothing gets buried, and offset each layer rather than setting bulbs directly on top of one another — the lower ones will find their way up, but they ideally won't have to shove a neighbor aside to do it.
Companion Plants: Topping Off Your Container
Since bulbs are buried, a fully planted pot of bulbs looks bare at the start of the season. In order to start your container off with some interest, you can plant cool season material right on top.
The key here is to plant your shallow-planted corms in the spaces between your plant material. Plants can be placed directly over the deeper planted bulbs like daffodils, tulips and hyacinth — they'll find their way up. I generally choose a thriller, filler and a spiller, but leave plenty of space for the bulbs to grow. Don’t get too caught up on doing everything exactly right - it’s fun to experiment!
As a final layer, I like to sprinkle Sweet Alyssum seed on top - one of my favorite flowers to grow for those in-between places.
Right after planting Spring display
Building Your Color Story
Color sets the tone and while there are "rules" to follow in terms of color theory (I personally like a contained palette that's either monochromatic or adjacent on the color wheel) — to each her own! Whatever direction you want to go, it's worth taking a moment to map out the colors that will be present at full bloom and make sure you’ll enjoy the total ensemble.
How to Care for a Lasagna-Planted Container
Light
Full sun — six hours or more. One thing working in your favor: spring bulbs do most of their growing before the trees leaf out, so a spot that goes shady in June can still be a great bulb spot in March. If you're in a warm zone like I am, a little afternoon shade actually buys you a few extra days of bloom, since flowers hold their color longer out of the hot sun.
Water
Water the pot in well at planting (3 separate passes with a watering can or hose until soil is fully moistened) — this signals roots to start growing. Through fall and winter, check your pot often and water when the top inch or two is dry. It feels strange to water a pot with nothing in it, but there's a lot happening down there: bulbs root all winter long, and containers dry out faster than beds even in cold weather.
Once shoots appear and the pot is actively growing, it'll want more more - an inch a week is the rule of thumb, but the best way to know is to check the soil by hand. Move the pot to a protected spot once the plants are going dormant - you want to protect the bulbs from rot - or remove the plants and replant your container for summer.
Freeze protection
Pots freeze harder and faster than ground does — a container is exposed to cold air on every side, while a bed is insulated by the earth around it. Here in 8b it's rarely an issue, but when we're headed into hard freeze territory, I keep pots against the house, move them into the garage/inside, or group them together and wrap the sides with a frost cloth. Just make sure to remove the frost cloth once safe.
Feeding
Mostly optional in year one. If you'd like to try keeping the bulbs for a second season, work a low-nitrogen bulb fertilizer into the mix at planting and scratch in a little more when shoots break the surface. When plants are blooming, you can top them off with a liquid feed.
If you’re growing in the ground - always get a soil test before applying fertilizer.
Squirrels
Squirrels are the worst. Some bulbs like tulips and crocus are candy to squirrels; and while daffodils, hyacinth, muscari and alliums are not - I'm convinced they're on a mission to sabatoge my garden anyway. Lay a piece of chicken wire over the soil surface after planting and cover it with mulch. The plants will grow right through it.
After the bloom
Deadhead spent flowers so the plant doesn't waste energy setting seed, but leave the foliage until it yellows and flops — that's the bulb's way to recharge for next year.
In my climate, tulips, ranunculus and hyacinth are a one-season affair, but daffodils, muscari and anemones can be lifted out and moved into the garden or stored in a protected spot over summer to return in future seasons.
For more on fall pots - click here to join the waitlist for the complete Fall Container Planting Guide with Easy Planter Recipes.
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