Most plant bulbs grow well in Massachusetts, which is in USDA hardiness zones 4 to 7. Plants with bulb-like root structures often are called bulbs, even though technically they may not be bulbs.They could be rhizomes, tubers or corms instead. No matter which type of plant bulbs you have, all have different planting requirements, and there are some planting guidelines that apply to most.
Determine what kind of bulbs you have. They are tender (e.g., dahlias) or hardy (e.g., tulips) in zones 4 to 7. Plant them in the spring after the first frost if they are tender. Plant them in the fall before the first frost, if possible, if they are hardy.
Plant the bulbs in a location that has full sun or partial shade. Check at the light requirements for your bulbs, but most will grow well in partial shade to full sun.
Turn over the top 12 inches of the soil with a hoe, tiller or garden rake and mix in 3 or 4 inches of organic matter such as compost or peat moss. Most bulbs prefer well-draining, enriched soil.
Plant the bulbs according to their needs. True bulbs and corms usually are planted 2 to 3 times as deep as they are in width. Rhizomes and tubers are planted closer to the soil’s surface. Spacing varies from bulb to bulb and should be spaced about the same size as their mature width.
Backfill the soil and tamp it down lightly to remove air pockets. Water the planting site slowly with 1 to 2 inches of water.
Spread 2 to 3 inches of bark or pine-needle mulch over the planting site, especially in zones 4 and 5. This is true for spring and fall plantings. This will help prevent the ground from freezing too fast in the fall and from freezing and refreezing in the spring.