Bulbs are a very economical way to ensure beautiful spring color year after year. The ideal time to plant bulbs is in the fall. This should result in very resilient, bright flowers for the spring.
Having a good soil base is essential for growing healthy bulbs. Make sure your soil’s clay content isn’t too high. If it is, simply add soil amendment. Till the soil amendment into the top 12 inches of soil. This should help break up the clay and make the soil more conducive for planting.
Recommended: Agromin’s Agromend soil amendment — a soil amendment specifically designed for clay soils. It helps keep heavy clay soils loose and workable, adds organic matter, is long lasting, helps get plants established and improves soil structure.
Phosphorous is a necessity to the bulbs’ root development. Mix a phosphorous fertilizer with the soil beneath the bulbs’ location so that it can benefit the roots.
For bulbs to come back year after year, you will need additional fertilizer. Mix five tablespoons of 10-10-10 fertilizer, plus two cups of bone meal per 10 square foot section. As soon as you see evidence of the plant sprouts, apply fertilizer. Don’t fertilize spring bulbs once they start flowering. This may rot the bulbs and shorten their life.
For summer and fall blooming bulbs, fertilize once per month from the time they start peaking out of the ground to the time they reach full bloom. Apply seven tablespoons of the 10-10-10 fertilizer, split over two or three applications. Monitor the pH levels of your soil. The ideal range for bulbs is a 6 to 7. For healthy bulb development, till bone meal into the soil when you plant the bulbs. You can buy pH level testing kits at most garden centers.
A basic rule of thumb is to plant bulbs at least twice as deep as the bulb is tall. Hyacinths, tulips and daffodils should be planted with the top of the bulb facing upward and the plate facing down. If you are planting several bulbs, you can simply loosen the entire bed of soil, press in the bulbs and cover with soil. This technique helps with drainage and allows the bulbs to last longer.
Keep in mind that bulbs planted in the fall need to take root before the ground freezes.
Once the bulbs are planted, the garden area should be covered with at least two inches of mulch. We recommend Agromin’s ES-2 mulch or Acorn Bark. The mulch helps to insulate the soil and retain the moisture.
Water bulbs immediately upon planting. As you water regularly, keep in mind that bulbs are typically planted six to eight inches deep and water needs to penetrate to the bulb. You can water with a soaker hose to keep the water off the bloom. Be careful — over-watering can cause the bulb to rot.
You may need to add some extra support to some of the blooming bulbs such as delphiniums and dahlias. You can add a support ring around a tall weak stem. You can also use stakes, but be careful when you drive the stake into the ground so as not to damage the bulbs or roots.
Digging and Storing Bulbs
You will know a bulb is dormant when the foliage turns brown and dies. This means that the roots that nourish the bulbs have also died.
Consider digging up and storing most of the flowering summer bulbs after they turn yellow. You can use a spade-like fork to dig up the bulbs. Wash the bulbs and spread them in a cool and shady place to dry. When they are dry, store them away from sunlight in a cool, dry basement, shed or garage at about 60° to 65°F. Be sure to inspect your bulbs for disease. Throw away any that are discolored or soft and keep the large, healthy bulbs for next year’s planting.