Crocuses and snowdrops speckling the winter lawn, tulips in every colour along a hedge, hyacinths and lilies in beds and pots: bulbs carry the garden from the coldest weeks into summer. Success turns on soil that never stays flooded, and on planting at the right moment — those that flower in spring go in during autumn, summer bulbs in spring.
– Spring-flowering > plant in fall
– Summer bulb > plant in spring
Recommendations for planting bulb flowers like tulip, hyacinth, crocus…
Avoid rocky, heavy and often-flooded soil types.
These would keep the bulbs from developing well, and prolonged flooding usually makes bulbs rot. If this is the soil you have, consider building a raised bed.
Rather than dropping grit into the bottom of each hole, where it can form a sump in heavy soil, dig coarse grit through the whole bed or plant bulbs in raised ridges.
Never set bulbs directly on fresh manure.
Required exposure depends on the species. Some bulb flowers, like Cyclamen, will dry out in full sun.
As a rule of thumb, the more sunlight a spot gets, the earlier bulb flowers there will bloom. Planting the same type of flowers in shade, part shade, and full sun can stage the blooming by up to two or three weeks.
Type the name of the plant in the Nature-and-Garden search box to call up the specific page for each and discover all of its characteristics.
In most cases, never plant bulbs closer than 4 to 6 inches (10 to 15 cm) apart.
But some plants like crocus and snowdrop can be crowded together since they are very small flowers.
Conversely, this distance must be increased to 8 to 12 inches (20 to 30 cm) for balisier or iris.
Good to know: you’ll get the most natural effect in your flower bed with the following trick:
For bulb flowers, randomness is often more appealing than regular, perfectly spaced flowers.
How much room a bulb needs depends entirely on how big it grows. Use this summary to space each type correctly before you start digging.
| Bulb | Spacing | Where it works well |
|---|---|---|
| Crocus | Can be crowded together | Straight into the lawn, for bright winter colour |
| Snowdrop | Can be crowded together | Very small flowers, so plant in tight groups |
| Most bulbs | 4 to 6 inches (10 to 15 cm) minimum | General rule for beds and borders |
| Iris | 8 to 12 inches (20 to 30 cm) | Needs noticeably more room than small bulbs |
| Balisier | 8 to 12 inches (20 to 30 cm) | Among the widest-spaced of the bulb plants |
| Tulip | 4 to 6 inches (10 to 15 cm) | Flower beds, along hedges, even pots on a balcony |
Whatever the spacing, scattering the bulbs by hand and planting them where they land gives the most natural result.
Use a planter, either a normal one or one specially designed for bulbs, or use a simple spade.
Dig a hole roughly 2 or 3 times deep as the bulb is high, and cover with soil. Take care to check that the entire surface of the bulb is in contact with the soil.
After that, mulch with a light mulch (thin layer of lawn clippings or other plant-based mulch).
Set each bulb pointed tip upwards, with the flat basal plate facing down.
Gardeners often add coarse sand or grit beneath bulbs in damp ground, though in heavy clay such a pocket can trap water, so improving drainage across the whole bed is more reliable.
Water thoroughly right after planting so the soil settles around the bulb and roots can grow into it; how much watering follows depends on the bulb type, your soil and the climate.
This is the perfect solution if the soil is really too heavy, or if you don’t have much space. For instance, growing potted tulip is very gratifying!
Most pots should have drainage holes, since bulbs left in soggy compost are prone to rotting, much as they are in waterlogged ground; without holes, water the container sparingly and carefully.
Layer big bulbs like tulips deep and small ones like crocus above them for weeks of bloom from one pot.
Pot compost dries out much faster than open ground, so check it through the growing season and water before the leaves flag.
You are now ready to plant bulbs and see beautiful flowers in your garden, great job!
