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Fall Bulb Planting Guide

Plant Now

For most gardeners, the first sign of Spring each year is the earliest flowers of crocus or snowdrops poking out of the seemingly empty garden. The real magic comes from the fact that there is so little work involved in creating this delight; and what a great way to get us inspired for the coming season!

First, keep in mind that a bulb actually contains the entire living flower in miniature form surrounded by “leaves” of stored food. All that they need to start growing is the cold dormant period that winter provides. Then, as the soil warms, up they come. The leaves get busy and provide the food which is stored for the next season.

Remember to treat each bulb with care. Keep unplanted bulbs in a cool, dark, dry place with good air circulation. Plant them as soon as the soil has begun to cool down, usually in late September or early October. Don’t wait too long, though, or the ground may freeze and abruptly end the planting season for you.

Enjoy Later

Since they are self-contained, bulbs will bloom virtually anywhere. All bulbs, except tulips, need full sunlight, however, avoid poorly drained locations where water may stand. The bulbs may rot. To ensure a good showing year after year, plant in a location which will get direct sun, especially in early spring. Bulbs will do very well under a deciduous tree where they will get sun before the leaves grow out. If the bulbs are planted in an fully exposed location, be sure the soil does not dry out during the winter and early spring, otherwise, the buds may dry up. City Floral recommends a months deep watering.

Planting is easy: Position bulbs the recommended depth, replace the soil, sprinkle bulb or flower fertilizer (2 lb/10’x10′ lot) over the area and water thoroughly.

When planting the bulbs, keep in mind their time of bloom.
Crocus: Between January snowfalls; minor bulbs in February and March
Tulips: Late March or early April through May
Daffodils & Hyacinths: Most of April
These times are somewhat dependent on weather and planting depth, but the species will always follow the same order. They aren’t hurt by the snow they may face.

Minor Bulbs 

The minor bulbs include snowdrops, glory-of-the-snow, aconite, pushkinia, grape hyacinths, and giant and species crocus. Plant them about 3″-4″ deep. Remember their blooms are small so they look better when planted in groups. They work best in rock gardens or in spots which are very visible. Don’t plant them across the yard or you may miss them completely.

Crocuses 

The difference between the species crocus and the giant crocus is that the species are smaller and bloom earlier. Plant both about 4″ deep. Again, remember that they look better when planted in groups.

Hyacinths

The next tallest group of bulbs is Hyacinth. Be sure to plant these later bloomers where you will be able to enjoy their marvelous fragrance. They should be planted 6″-8″ deep, and will get up to 10″-12″ tall. Planted in a row, maybe along a walkway, they make an excellent border.

Tulips

The most popular bulb flower is the tulip. They range from the 6″ miniatures to the 24″-30″ late tulips. Not all tulips bloom at the same time; their season depends on the weather and the depth at which they are planted. In Colorado, tulips should be planted about 6″-8″ deep.

The earliest bloomers are Botanical Tulips:
Kaufmanniana: earliest, 6″-8″ tall, huge flowers which are mottled purple
Fosteriana: (Emperor) almost as early but much taller
Greigii: very short, corrugated-esque leaves, very large-flowered

The early tulips bloom next. There are both single- and double-flowered early tulips and are fairly moderately sized. These varieties are great for forcing. (Please ask us for our forcing guide!)

Normally in Denver, early tulips bloom in late March-mid April, mid season tulips bloom mid- April to early May, and late tulips early-mid May.

Triumph Tulips are crosses between early tulips and Darwin tulips, and bloom between the two. They have one outstanding characteristic: their foliage ripens and dies down much faster than most tulips so annuals can be planted among them quite early. Some also force well.

About the same time as Triumphs, the Darwin Hybrid tulips bloom. They have the most classically shaped flowers. Darwin Hybrids are about 10 days earlier than the Darwins. Both have sturdy stems, good for cutting.

Daffodils 

Also blooming at the late end of the season are the Lily-flowered tulips and the Parrot tulips. The large late double tulips are short but showy. During April, daffodils bloom. Technically, daffodils, narcissus, and jonquils are different names for the same group of bulbs. Usually, however, “daffodil” is used for the large trumpet-flowered types, and use “narcissus” for the clusters of small flowers. Daffodils are the hardier of the bulbs and may multiply over time. Plant daffodils 6″-8″ deep, except super -mini and mini varieties should be 3″-4″. The large trumpet daffodils bloom first, followed by the short cupped and doubles. The narcissus with the multi-blooms are usually last. However, in Denver, all daffodils tend to bloom in April.

Late Bloomers

Let’s not forget some of the unusual novelties which bloom later in the season. Allium, Fritillaria (Crown Imperial), Bearded Iris, and liles which bloom as late as August.

A Few More Things

-Can precede summer annuals, which can be tucked around their ripening foliage
-Achieve a natural look by tossing the bulbs and planting where they land
-Best results: formal beds of one variety
-Don’t remove foliage until ripened-turned completely brown and fertilizer should be applied in fall and when leaves emerge

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