Naturalizing bulbs in grass
For naturalizing bulbs in grass you need to choose bulbs that are adapted to the use you wish to put them to. Choose an area of grass in your garden that you don’t mind leaving it unmown until early summer when the bulb foliage will die back naturally. For planting bulbs individually in the grass, scatter the bulbs on to the grass area you have chosen in a random fashion and plant them where they fall, trying to allow a distance of about 8-20 cm between each one.
Dig a deep, square hole of about a spade’s width and about 25 cm deep, depending on the size of the bulbs you are going to plant. You may need to go deeper than one spade’s depth if the bulbs are really big. Put a layer of grit or sand in the bottom of the holes then plant the bulbs, base down. Cover the bulbs with loose soil and replace the top divot. Firm down gently.
If you want to plant a lot of bulbs individually, you can use a special bulb-planting tool to save time. This tool takes out a core of soil. Push the bulb-planter into the soil by twisting it a little if the ground is hard then pull it out with the core of soil. Release the core of soil and place the bulb at the bottom of the hole. Pull off a little soil from the base of the core to allow the depth of the bulb, then replace the core in the hole. Firm gently and fill any gaps with sieved garden soil.
For small bulbs you can naturalize them in a small area of grass. If you have a lot of small bulbs, like crocuses or winter aconite, and you only have a limited are to plant them, use a spade or half-moon edger to make an H-shaped cut. Slice beneath the grass with a spade until you can fold back the turf for planting the bulbs. Do this with care so you get an even turf that can be folded back without cracking.
Loosen the ground before planting the bulbs, as it may be very compacted. You can also work into the soil a slow-acting fertilizer, like bonemeal. Don’t plant them in rows or specific patterns, just scatter them on to the soil and plant them more or less where they fall, because you want them to look natural. For larger bulbs make deeper holes into the ground with a trowel and plant them so they are covered with about twice their own depth of the soil. Use a spade to dig out a hole for a group of bulbs. Firm the soil then return the turf back in its place. Firm again to make sure it is flat and water well if the weather is dry to make sure that the grass will grow again quickly.
Naturalizing bulbs in beds and borders
Areas that are regularly cultivated for planting seasonal bedding plants are not suitable for naturalizing bulbs because you might dig them up by mistake over their dormant period, unless their place is clearly marked. You can use areas that are left relatively undisturbed, like places between shrubs and trees. These places can be effectively planted with naturalized bulbs. They will do particularly well between late-leafing deciduous specimens, where they can get plenty of light during early spring.
Naturalized bulbs also combine well with late emerging perennials and hardy ferns, as these will disguise the yellowing bulbs foliage as they grow. For these places you can choose bulbs like: winter aconites, anemones, bluebells, grape hyacinths, crocuses, daffodils, fritillaries, snowdrops and chionodoxas.