Plant Fall Bulbs for Early Spring Colour
Joe Gadbois, September 19, 2024
When I was a new gardener as a kid, it didn’t take long for me to discover the joy of fall bulbs. Seeing them appear in garden centres in the fall added excitement to what would otherwise be… let’s just say not my favourite season. I’ve learned to appreciate the fall, and gardeners that don’t love winter like me can look forward to spring by planting fall bulbs.
What are fall bulbs, and why should you plant them?
These plants often come from climates that have seasonally available moisture in the spring, followed by hot, dry summers. They’ve developed underground storage organs for water and nutrients, so they can retreat underground during those hot and dry summers. Taking advantage of a short growing season, these plants will emerge as soon as the ground thaws and are the harbingers of spring, often blooming when there is still snow on the ground or poking through a fresh blanket of snow. In my opinion, fall bulbs are essential for extending the bloom season in the garden. Plant a selection of fall bulbs, and you’ll have tons of colour in April or even earlier in central Alberta, depending on the spring. Of course, these colourful flowers are also an early source of food for pollinators.
Fall bulbs can be easily tucked in between existing perennials and shrubs and will put on their show before most perennials emerge and shrubs leaf out. By the time the bulbs start to disappear, the other plants can take the spotlight.
Some of our favourite flowers are only available as fall bulbs, such as tulips, daffodils, crocus, and large flowered allium. While you can buy some of these as forced potted plants in late winter or early spring, usually bulbs that have been forced won’t survive in the garden afterwards, so to keep them coming back year after year, you’ll want to plant fresh bulbs in the fall. The best varieties of garlic for planting are only available in the fall, and trust me, homegrown garlic is far superior to store bought. It’s so easy to grow and one package will give you a really nice harvest. You’ll never buy store bought garlic again after you’ve grown it yourself – you’ll become a garlic snob!
Compared to buying potted perennials, bulbs are inexpensive, and they are very easy to plant and care for. Let’s go over how to do that.
Planting and Caring for Fall Bulbs
Most fall bulbs should be planted in mid-fall, when temperatures have cooled to below 20C for daytime highs. Some gardeners will wait until the first frost before planting. Just keep in mind, they need at least a few weeks to get rooted in before the ground freezes. I recommend planting the following as soon as possible after purchase: lilies, fritillaria, snowdrops, and any fall flowering bulbs such as cyclamen and colchicum. Snowdrops, anemones, and winter aconite should be soaked in water overnight before planting.
Dig your hole 3 times deeper than the height of the bulb. For example, if you’re planting a tulip bulb that is 2 inches tall, dig your hole 6 inches deep. Add a handful each of compost and bone meal to the bottom of the hole and mix it together lightly with some soil at the bottom. Make sure your bulb is oriented properly. Most bulbs have a roughly teardrop shape, with a flat bottom and a pointed top. The pointed side faces up. In some cases you will have a tuber, which will often be rounded on the bottom and will have a visible crown or a dip on the top, which is the part that faces upward. Place the bulb in the hole, backfill with soil, and compress lightly, then water it in well. If the soil is quite dry, I like to water it when the hole is half full, and water it again when the hole is filled. This ensures the water gets all the way down to the bulb.
A couple special mentions: Fritillaria bulbs will have a hole in the centre on the top side and should be planted at a 45-degree angle so that water doesn’t collect in the hole and cause the bulb to rot. Cyclamen tubers should be planted at a slight angle as well, and no more than about an inch deep.
Special winter protection is not required when you’re planting in the ground. If desired, up to 2 inches of mulch such as bark can be applied over the soil. All the fall bulbs we carry at Greenland are winter hardy in central Alberta, which I know from seeing them survive many years in my own garden or other local gardens. Keep in mind that online sources from the US and other warmer climates often rate plants at higher zones than they will actually survive in, because they simply don’t know what plants can survive in zone 3 and 4. Zone 3 is a small market!
In the spring, as the bulbs emerge and flower, you don’t need to start watering until the soil dries out after the melt. Areas against the house often dry out quite quickly. I don’t fertilize my bulbs – I simply add more compost and bone meal to the soil every year. If desired, 15-30-15 or similar can be applied once plants are actively growing. Do not apply fertilizer after blooming. Allow the plants to yellow off naturally before cutting the foliage off. Water is not required once they start to yellow.
Bulbs seldom need to be divided, but if you need to move them or want to give some bulbs away, fall is the time to do it. Asiatic lilies often crowd themselves after a number of years and stop blooming well until they are dug up, separated, and replanted in smaller groups.
Types of Fall Bulbs to Try
Hybrid Tulips
This spring classic is sure to bring a smile to your face, with innumerable colours to choose from, as well as special forms like double, fringed, and parrot types. Plant both early and late blooming types to extend the season. They also make a gorgeous cut flower. Keep in mind that these types of tulips are best treated as annuals – dig them out and plant fresh bulbs each year as they tend to only bloom well the first year in the ground. Best grown in full sun.
Botanical Tulips
Also called species tulips, these are shorter plants with more open flowers which, unlike most hybrid tulips, will perennialize and naturalize. These are great for rock gardens and border edging. Best grown in full sun but will tolerate some shade.
Daffodils
This favourite group includes many different types which range in height, flower size, number of flowers, and colour. They perennialize well and will last for many years in the garden and are a great choice for both sunny and partly shaded areas.
Crocus
Some of the earliest flowering bulbs, these burst into bloom near ground level as soon as the snow melts. They are a great choice for naturalizing and can even be planted in the lawn with an aerator tool. They will flower before the lawn greens up, and by the time it needs the first mow they will be finished and can be safely mowed with the grass. Also great in rock gardens and borders. Additionally, there are fall blooming types available; all are best in full sun but will tolerate some shade.
Allium
The large-flowered alliums bloom in summer, long after most fall bulbs have finished. They will wow you with globe-shaped flowerheads up to 8 inches across! Most varieties will start to yellow off as the flowers open, so be sure to plant amongst perennials and shrubs that can hide any unsightly foliage. ‘Ambassador’ (pictured) is noteworthy for having more persistent foliage. These guys are best in full sun.
Grape Hyacinth and Siberian Squill
We have these planted along the front of the main building at Greenland, and each spring hundreds of visitors remark how beautiful they are, and we have to tell them to come back in the fall! Planted in large drifts, the dazzling blue of these short plants is eye-popping. Combine with yellow daffodils for even greater effect. They naturalize freely and will work in sun to part shade.
Odds & Ends
Did you know there are species of Cyclamen that are hardy in Alberta? C. hederifolium is one of them. The flowers and beautiful marbled foliage both emerge in fall and the leaves persist through the winter, disappearing in summer. It’s a great plant for shady areas.
Crown imperial (Fritillaria imperialis) is a lily relative with a stately “crown” of blooms that appears far earlier than lilies. The entire plant smells like a skunk. It needs good soil drainage in sun to part shade.
Trout lily or dog’s tooth violet (Erythronium dens-canis) is a fun one to try in a semi-shaded area. It has beautiful flowers and mottled leaves.
Garlic
Split garlic heads into individual cloves when planting (do not peel the skin), and space the cloves 6 inches apart. Following the 3x depth planting rule, you are normally planting about 3 inches deep. Plant in well-drained soil in a sunny location. Do not be alarmed if they start to emerge before winter – this is not uncommon, and they will be fine!
If you’re looking for medium to spicy and complex flavours, there are many good choices such as Duganski, Metechi, and Purple Glazer. For a sweeter and less spicy flavour, German White is a good choice.