Spring bulbs are the cheapest thing you will ever do to a garden and one of the few jobs where the timing genuinely decides the result. Get them in during the right few weeks and they mostly look after themselves for years. Leave them in the bag on the shelf until February and you will get leaves and not much else.
The dates below are the RHS's, not mine, and they are worth following because bulbs are not really planted for spring — they are planted so the roots have time to get down before the ground goes cold.
The dates
Daffodils, crocus and hyacinths: preferably by the end of September. These want the longest run at making roots. September is early enough that the soil still has some warmth in it, which is the whole point.
Alliums: September and October. They flower later than the others and are more forgiving about exactly when they go in.
Tulips: November. This is the one that surprises people, and it is genuinely the RHS's own recommendation rather than a piece of garden folklore. Tulips do not need the long autumn root run the daffodils want, and going in late keeps them out of warm, wet soil during the weeks when fungal trouble is easiest to pick up.
You will read in a lot of places that a November planting is specifically to dodge tulip fire because the cold "kills the fungus". That is not what the RHS actually says, and it is worth knowing the difference — see below.
How deep, and how far apart
Two rules cover nearly everything:
Two to three times the bulb's own height. A bulb 5cm tall goes in a hole 10–15cm deep. In a pot, go to three times.
At least twice the bulb's own width apart.
Deeper is the safer error. A shallow bulb dries out, gets forked up by whoever plants bedding next spring, and in a lawn it gets scalped by the mower. Too-shallow is the commonest reason a clump comes up blind after a couple of years.
Point the nose up. If you genuinely cannot tell which end is which — some crocus and anemone corms are a coin toss — plant it on its side. It will sort itself out.
Drainage matters more than soil quality
Most hardy bulbs, tulips and daffodils included, come from places with dry summers, so they want a warm sunny spot with drainage that works. Bulbs sitting in wet ground over winter rot, and no amount of feeding fixes it.
On heavy clay — and a lot of gardens around Ledbury and the Malverns sit on exactly that — a handful of grit under each bulb makes a real difference, or plant into a raised bed or a pot instead of fighting the ground. If you want to know why the drainage on your patch behaves the way it does, clearing an overgrown garden covers reading the soil before you commit to anything.
Tulip fire — the one that costs you three years
This is the reason to look at your bulbs before they go in rather than after.
Tulip fire is a fungus, Botrytis tulipae. The leaves come up twisted or fail to develop, brown dead patches spread across them, and in a bad year the bed looks scorched — which is where the name comes from. In damp weather a grey fuzzy mould grows over the dead areas.
What makes it worth naming here is how it survives. The fungus makes small black seed-like bodies that sit in the soil, and the RHS is blunt about what that means: do not plant tulips for at least three years in a site where tulip fire has occurred. There are no chemical controls available to a home gardener, so the rotation is the control.
So the job at planting time is two minutes of looking. Discard any bulb with sunken lesions, black specks under the papery skin, or soft patches. Give them a bit of space rather than packing them in, because the spores travel plant to plant and airflow between them slows that down.
In grass
Daffodils, crocus and snowdrops in open grass is the version of this that pays back the most, because it is the one place you plant bulbs once and then genuinely never touch them again.
The catch is the mowing. The foliage has to be left alone until it has properly yellowed — roughly six weeks after flowering — because that is when the bulb is refilling itself for next year. Cut it green and you get a smaller flower the following spring and nothing at all the year after. Plan for a rough patch of lawn until about mid-June, and site the drift somewhere that does not matter for the first cut of the season. There is more on how that fits the year's mowing in the first lawn cut of the year.
If you would rather it was done
Bulb planting is one of the few jobs where a couple of hours in autumn buys something you will see every spring for a decade. If you want a drift put in properly — right depth, right spacing, and the bulbs checked over before they go anywhere near your soil — that is a straightforward visit to book.