Many of the bulbs that flower in late winter, early spring and mid spring, such as Galanthus or snowdrop, Eranthis or winter aconite, crocuses, anemones, most daffodils and some Erythronium (dog's tooth violet), thrive in grass, coming up year after year and self seeding themselves.
These robust bulbs can withstand competition from grass roots and are much more suitable for this type of planting. Early in the year, when the grass is short and competition for light is not a problem, the pointed shoots cut through the turf quite easily.
How to plant bulbs individually? First, throw the bulbs on to the turf in a random fashion and plant accordingly, but try to allow a distance of about 7.5 to 20cm or 3 to 8in between each one.
Then, dig a deep, square hole, of about a spade's width and about 25cm or 10in deep, depending on the size of the bulb. You may need to go deeper than one spade's depth. After that, plant the bulb, base down and the neck or nose pointing up.
Cover the bulb with loose soil and replace the top divot. Firm it down gently.
How to plant bulbs in large groups? First, dig a trench a spade's width and fold the turf backwards on itself. Use a trowel or dig down to a depth of about 25cm or 10in. Then, plant Narcissus poeticus var recurvus with Camassia Leichtlinii, placing them alternately about 20cm or 8in apart.
Next, fill in with loose soil so that the tops of the bulbs are covered. Replace the turf and firm down well with the heel of your boot.
Although it will look untidy, allow six weeks to pass after flowering before cutting the grass where bulbs have been growing. This will ensure good results for the following year. The grass will soon recover.