Plant spring-flowering bulbs such as tulips, daffodils and crocuses in the fall, once the soil has cooled but before the ground freezes, burying each bulb about three times as deep as it is tall. For most of Canada, that window runs from late September to late October, which means early October is the time to get them in the ground.
Bulbs need the cold months to bloom. They have to put down roots before freeze-up and then sit through winter’s chill before they push up in spring, so planting too late leaves them little time to settle in. The National Capital Commission advises planting tulip bulbs when soil temperature is below 10 to 15 C, before the ground freezes, usually between late September and late October. Guelph-Wellington Master Gardeners suggest late September or early October for narcissus (daffodils), alliums and small bulbs, with tulips going in as long as the soil is still workable. Gardeners in colder regions should lean toward the early end of that window, since the ground freezes sooner. Here is how to do it, step by step.
- Pick a well-drained, sunny spot. Bulbs prefer well-drained soil, and most need about four to six hours of sun a day, according to Guelph-Wellington Master Gardeners. Shade-tolerant types such as daffodils and Spanish bluebells can handle partial shade, for example at the edge of a tree’s canopy. If water pools in the spot after rain, pick another location or improve drainage first. Breck’s, a bulb supplier, recommends breaking up hard subsoil and adding coarse gravel or broken stone where water collects.
- Wait for cool soil. The NCC’s guidance is to plant once soil is below 10 to 15 C, and before the ground freezes.
- Dig to the right depth. The standard rule, repeated by all three sources, is to plant two to three times as deep as the bulb is tall. Breck’s puts large bulbs such as tulips and daffodils at about 15 cm deep and small bulbs such as crocuses at 8 to 10 cm. The NCC suggests 15 to 20 cm for tulips. Guelph-Wellington Master Gardeners give a simple example: a daffodil bulb 5 cm (two inches) tall needs a hole about 15 cm (six inches) deep, while miniature varieties need 8 to 13 cm (three to five inches).
- Loosen the soil at the bottom of the hole. The NCC recommends loosening the base and mixing in bone meal according to the package directions. Guelph-Wellington Master Gardeners say a balanced 10-52-10 fertilizer supports spring growth. Follow the label on whichever product you use.
- Set each bulb pointed end up. The pointed tip is where the stem emerges, and the flatter side is the base. If you cannot tell which end is which, Guelph-Wellington Master Gardeners say to plant the bulb on its side.
- Space them properly. Breck’s suggests 8 to 15 cm between large bulbs and 3 to 5 cm between small ones. The NCC says tulips should be at least 5 cm apart. Planting in clusters of 7 to 15 bulbs, rather than single file, gives a fuller look, the NCC notes.
- Cover, then water well. Backfill the hole and water thoroughly to settle the soil and encourage rooting before the ground freezes. Breck’s cautions against overwatering, which can cause rot.
- Mulch and protect against wildlife if needed. In very cold climates, Breck’s recommends covering the bed with mulch or hay to protect the bulbs. To keep squirrels and other rodents from digging them up, Breck’s suggests laying a piece of chicken wire over the planting area. The NCC adds that planting tulips alongside daffodils can help, since wildlife typically avoid daffodils.
A few planning choices will stretch the show. The NCC suggests mixing early, mid-season and late-blooming varieties, and varying heights and colours, to extend the flowering period through spring.
Once planted, there is little left to do until the shoots appear in spring. If bulbs are still in a bag in November, check that the ground is workable and, if it is, plant them and water them in.
Sources: National Capital Commission, “Tulip planting season is here”; Guelph-Wellington Master Gardeners, fall bulb planting guidance; Breck’s Canada, “How to grow bulbs guide.”
