Easy Tips for Layering Bulbs to Make a Bulb Lasagne

How to layer bulbs in pots as a bulb lasagne for a succession of beautiful spring flowers from at least February to May. It involves layering potting mix, spring bulbs, and drainage materials in pots to set on your balcony, porch, or just outside your front door. This is a fantastic autumn gardening project that will set your garden up for spring color.

Though you may well have plans to plant bulbs in your flower beds and lawn, think about putting some in pots, too. They look stunning in bloom and can also cheer you up on a cold March day. In planters, bulbs can be crowded in and layered and create displays that are more impressive than the ones in the garden. The technique is called a bulb lasagne or lasagna planting, and you create it much in the way that you layer the well-known food dish. Instead of pasta, cheese, and sauce, you layer potting mix, bulbs, and drainage materials. You can get many more flowers in a small space this way and create beautiful, low-maintenance displays from late winter to late spring.

For me, the first of the year’s flowers always emerge from planters next to the front door. They never fail to put a smile on my face even though the days are still dark and are a reminder that warmer days are on the way. Late winter and early spring can be a low point of the year, but a bright display of flowers can make you feel more energetic and positive. They certainly do for me, so that’s why a bulb lasagne is always on the menu for me. You plant them in autumn and wait for the show to start early the next year.

Lasagne Planting for Continuous Spring Blooms

The idea behind layering bulbs is to create a planter that will have flowers blooming at all times in early spring. The earliest bloom time could be snowdrops, and it could end with a burst of allium flowers in late May to June. The way you accomplish this is by layering as many bulbs as possible at different depths in a single pot. As they grow, they gently push past one another on the way up and bloom in procession. Most bulb lasagnes have two to three layers of bulbs, but you could have more if you’re using a larger pot.

Choose your flowering bulbs wisely, and your single container can begin blooming as early as January in mind regions. Those delicate blossoms can be followed by daffodils, scillas, hyacinths, and tulips and bloom with late-season bulbs right into May and early June. The flowering time shown below may be a little earlier or later, depending on your climate, but it shows the general idea and planting depths.

Choosing Flower Bulbs

You can source small bags of inexpensive bulbs at many garden centers or even at supermarkets. For higher quality bulbs, bulk bulbs, and a wider range of types, colors, and shapes, order through a reputable bulb nursery or distributor. My go-to company for bulbs in Britain is Sarah Raven, and in the United States, it’s Nature’s Hill Nursery and other small nurseries. If you have an option for ordering Dutch bulbs directly, I recommend you do so since that’s where many bulbs are grown commercially. Here are some of my picks for flowers to plant in your bulb lasagne.

• Snowdrops
• Crocuses
• Dwarf iris (iris reticulata)
• Hyacinths
• Anemones
• Daffodils (narcissus)
• Tulips
• Grape hyacinths (muscari)

Materials for a Bulb Lasagne

To create a bulb lasagne, you’ll need a few “ingredients” aside from the flower bulbs. First, you’ll need a pot at least 1-1.5 feet in diameter and 15″ deep. Ensure that it has drainage holes at the bottom. You’ll also need a free-draining potting mix. Mix one part perlite or horticultural grit with two parts compost for the DIY version. You may also want to mix in bulb fertilizer to help the bulbs to grow healthily. With so many bulbs in one pot, it’s best to supplement the potting mix.

Before you begin layering potting mix and bulbs, you can fill the bottom of your pot with broken pot shards, shale stone, or gravel for drainage. You can also use fine gravel or horticultural grit to finish the top layer of compost. This is optional, but it looks nice, stops weeds from growing, and helps stop the potting mix from eroding out during winter and while watering.

Fill the Pot with Drainage Materials

The video below shares how I’ve planted my Belfast sink with two layers of bulbs. It’s a bright and beautiful planting that I’ve allowed to bloom two years in a row. I’ll begin the process of replanting it this autumn, though.

If you’re ready to go with your materials and bulbs, you can start by filling the bottom of the pot with broken crocks or about an inch of gravel. This bottom layer will help keep the soil above it in place and potentially better drained, but at least one study says that it’s not necessary. Bulb rot is a real worry, with bulbs sitting around in potentially waterlogged soil in winter, so it’s best to take precautions against this happening. Free draining potting mix helps, as does setting the pot up off the ground with pot feet in winter. This is something you should do anyway for terracotta pots to stop them freezing and cracking during cold periods.

Plant the Deepest Bulbs

Add a layer of compost over the drainage materials about three inches deep. Next, lay out the first layer of bulbs. These will be the ones that need the deepest planting space, and the bulb packaging should tell you just how deep they should be. These bulbs are usually relatively large. Space them out so that no bulbs are touching, and remember that the pointy ends of the bulbs are the tops. Sometimes, bulbs will already be sprouting, and that will let you know how to place them.

After they’re laid out, cover the bulbs with another layer of compost. The compost can just cover the tops, but how deep you cover them is dependent on how deep the next layer of bulbs should be in the pot. Refer to your own bulbs for guidance on how deep this layer should be. If you’re not sure, plant them a little deeper than you might originally think. Bulbs that are planted a little deep just have to work a little harder to get up in spring, but they tend to make it.

Plant the Second Layer of Bulbs

Next, layer bulbs that need less planting depth in a middle layer, and try to space them out so that they don’t sit directly on top of the bulbs below. You can see in the photo above that a couple of the hyacinth bulbs from underneath are just peeking through the compost. When your second layer of bulbs is spaced out, cover them with another layer of compost. Add a third layer of bulbs on top of that, then cover with more compost. You could even add a fourth and fifth layer if your pot is deep enough.

Finish the Top with Fine Gravel

Finish the top of the container with a fine layer of gravel or horticultural grit about 1/4″ to 1/2″ in depth. This last layer serves several purposes: it keeps the container from drying out, it helps keep soil from eroding out, it stops weeds from taking root, and it also looks nice. The bulbs below will be able to push their way through without any issue at all. When you’re layering the grit or gravel on top, make sure to leave around 1/2″ of space between it and the top of the pot.

Wait for the Bulb Lasagne to Bloom

For the autumn and winter months, your container will look unexciting unless you also plant the tops with winter bedding plants such as pansies and violas. That’s why I tend to move it to a place that’s out of sight. If you live in a place with cold and snowy winters, consider placing it in a greenhouse or polytunnel over the winter. Bulbs are pretty hardy, but being above ground gives them less protection from cold, and they might not survive otherwise. Since we have very mild winters here, I leave my containers outside year-round.

In late January, I’ll take the container out of hiding and set it someplace I’ll walk past daily. My front door or the back patio, usually. It’s such a delight to see the first succulent green leaves popping through the gravel! It’s a sure sign that spring is on its way. The first to come up are usually crocus and snowdrops, then anemones, daffodils, and finally, tulips. Consider how each of the flower colors will look together when choosing bulbs.

How to Care for a Bulb Lasagne

During the time that your plants are growing, keep the compost moist by watering it every day. Bulbs are something that most choose to replace every year, especially in containers. That’s because each bulb produces offsets (babies), and the container can get overcrowded. An overcrowded container often leads to less and less consistent blooms. This also happens when the potting mix becomes depleted of nutrients.

If you want to keep the bulbs to replant elsewhere in the garden, just follow a few steps. As the flowers begin to go over, deadhead them, but don’t cut any of the green foliage. The leaves need to soak up as much sun energy as possible. In late spring, your display will die off completely, and it’s then that you can gently pull the brown leaves out. Set the pot somewhere until autumn, when you should empty, organize, and replant the bulbs in the border or lawn. Then, it’s planting the container up again with new bulbs for a lovely new display the following spring.