A. Spring-flowering bulbs such as tulips and daffodils must be planted in the fall or early winter to bloom in spring because they require a long period of cool temperatures to spark the biochemical process that causes them to flower. In fall, it's important to get them into the ground before the ground freezes.
Not all bulbs should be planted in the fall. Dahlias and gladiolus should be planted in the spring, for instance, while daffodils and tulips do well when planted in late summer or early autumn. Here is the rule of thumb: If you are planting a bulb that blooms in the spring, plant it in the fall.
If the plants received sufficient cold in storage, they will eventually flower for you this spring. If not, you will just get leaves but next year you should be rewarded with blooms. Or you can force them into bloom. Pot up the bulbs and give them 12 to 15 weeks of cold (35-45 degrees) treatment.
Planting bulbs too early can leave them susceptible to rot. If you put them in the ground in late August or early September, they might even be tricked into thinking its spring, and try to bloom! If you plant too early, they won't bloom when they're supposed to.
Fall Bulbs should be planted as soon as the ground is cool, when evening temperatures average between 40° - 50° F. Ground temperatures reaching 40° - 50° F during fall is most common in cold climates (zones 1-7), generally 6-8 weeks before the ground freezes.
No, bulbs should not be soaked before planting because they are prone to rotting. Bulbs have tiny roots at the base and the idea behind pre-soaking is that perhaps the roots should be hydrated before planting. But, when planting in fall, there should be adequate moisture in the soil to provide what the bulbs need.
Water well when you plant the bulbs in fall as this will stimulate the roots to begin their growth. Keep the soil moist over the winter and continue throughout the blooming period as necessary. Stop watering about 3 weeks after the blooms have passed and allow the foliage and stems to die back.
Do I need to dig up my bulbs or can I leave them in the ground? Spring-blooming bulbs that are winter hardy, such as tulips, daffodils and crocus, can be left right in the ground. Summer bulbs such as dahlias, tuberous begonias and calla lilies, will not survive cold winters.
Store your flower bulbs in a dry place until you're ready to replant them. Aim for a storage temperature of 45 to 50 degrees Fahrenheit, such as a garage or refrigerator. Store tropical bulbs in a slightly warmer area.
Dried-out bulbs won't sprout when replanted. Store them in a dark location in a shed or garage where temperatures remain above freezing.
Plant Bulbs Deep Enough
Generally, dig a hole two to three times deeper than the bulb is tall. So if you have a 3-inch-tall bulb, dig a hole 6 to 9 inches deep. Of course, there are always exceptions, so check the planting directions that come with the bulbs for more information.
Adding a granular fertilizer in the fall and when they first start to shoot up in the spring can help with flower production. For gardens with poor soil, amending the soil with compost, and adding a granular fertilizer at the time of planting will give those bulbs an extra boost of nutrients.
Most bulbs should be planted after a hard frost, usually from mid October until the ground freezes.
The roots will then be able to supply the tops with water and nutrients from the soil. Waiting until spring to plant the bulbs will not satisfy these requirements, so spring-planted bulbs will likely not bloom this year. Saving the bulbs for planting next fall is not a wise choice either.
The most important reason to plant bulbs in November is that the temperatures are usually ideal for planting bulbs! Bulbs are simple for the most part. They need sun, air, water, and the right temperatures. Fall bulbs need cold temperatures to produce a flower bud.
The reason bulbs are so popular at this time is because they need to be planted in fall in order to perform their best. The soil is still warm enough to promote early root growth and a chilling period is still ahead, an essential element to a great spring display.
Many bulbs readily multiply by producing offsets without any help from the gardener. But as well as taking advantage of this, it is quite simple to grow more of your favourite bulbs using just a few other techniques, including scaling, bulbils, seed and division.
Bulbs planted in the Deep South, the desert Southwest, and most of California (more or less from the San Francisco Bay area south) do not get the cold they need. To perform well, they must be placed in a refrigerator (not a freezer) for 6 to 12 weeks before planting.
Short-lived bulbs: Most properly planted and cared-for bulbs will flower well for 3-5 years and beyond, but some thrive only for a couple of years or even one season before needing to be replaced.
The trick to ensuring bulbs are safe and happy all winter long is to keep them uniformly cool. So after you plant, it's valuable to put mulch on top of the soil. Not only does mulch keep the bulbs uniformly cool, but it also inhibits weed seeds by cutting off the light that encourages germination.
Soak fall-planted bulbs for 12 hours in warm water before planting. This moisturizing method works with tunicate-type bulbs (neatly enclosed round or teardrop-shaped bulbs) and is not suitable for lily or other bulbs with loose, fleshy scales.
There is no real reason to dig up tulips bulbs each year, or at all. Most gardeners leave their bulbs in the ground where they were originally planted, and, are left to rebloom. Sometimes gardeners will dig up tulip bulbs but only when the plants seem to have offered fewer flowers.
Bulbs will easily grow through 4 inches (10 cm) or even more of mulch as if it weren't there. Bulbs do this in the wild too, pushing their way up into the light, first through the soil, then the plant litter that covers the ground. Perennials do just the same thing, by the way.
Cover with soil and a light layer of mulch. Newly planted bulbs should be watered well to get settled in. If needed, protect bulbs from critters by staking down wire mesh or chicken wire over the beds or planting them in bulb baskets or wire cages.
First, it's important to fertilize when you plant the bulb. And you don't need anything fancy, Jim says, so don't overthink it. Use a good, balanced fertilizer (10-10-10, for example). The brand isn't as important as the balance of nutrients.