It is November and the temperatures are more in line with what they should be at this time of year, so it must be time to plant the spring flowering bulbs.
We plant these bulbs in late fall and early winter so they will have time to experience things that will affect their ability to produce their flowers in the spring.
They will need moisture, absorbed from the soils around them, to begin to break their dormant state and begin to establish their roots in the soil below. Equally important are cold winter temperatures. Most of these bulbs originated from the Netherlands or other cold parts of Northern Europe. They need the cold temperatures to feel “at home” in their new location.
Frigid soil temperatures will trigger a response in the metabolism of the flower bulb that begins the long process of sending up new leaves that are soon followed by the attractive flowers we all enjoy after a winter of mostly brown vegetation. This process is known in the trade as chilling.
We see a lot of plant foods and fertilizers for bulbs in the fall. The primary ingredient in these products is phosphorus in one form or another. It is tempting to think we must use these fertilizers to see those colorful displays next spring, but that is not entirely true.
The bulbs already have everything they need stored up in the nice compact little ball you put into the ground. Just add soil, water and cold temperatures and the bulbs will flower.
However, once they have flowered their energy reserves will be almost depleted. Allowing the foliage to stay for a few weeks after the flowers are gone will help the bulb replenish some of the energy it will need the following year, but adding a little bulb food in the fall or next spring will give them a boost. It all depends on the future of the flower. If you plan to keep it as a more permanent piece of your landscape, then feeding will be helpful, but go light. Too much plant food can damage the bulb or prevent it from growing anything more than just leaves. The package the bulb food comes in has instructions; it is always a good idea to read and follow those.
When planting, always remember the bulbs should point up toward the sun. The roots always go on the bottom. Most bulbs have a pointy end (the one that goes up) so this is easy to see. Some bulbs, such as anemones, do not have an obvious top. Try to examine each bulb closely to find a trace of where the roots were attached and use that as a guide, placing the roots on the bottom.
Planting depth is important to the success of growing bulbs. Too deep and they will not break through to the soil surface. Too shallow can result in winter freeze damage. Most guidelines will say to plant the bulb so the bottom is 2 ½ times the width of the bulb below the soil surface. My own experience is that as long as there is at least an inch of soil over the top of the bulb it will grow just fine.
You can dig a separate hole for each bulb or you can excavate a large area, place the bulbs, then cover with soil. Be sure to water well to settle the soil around the bulbs. If additional planting will take place over the winter near or among the bulbs, each one can be marked with a colored golf tee to mark their locations.
One nice thing about many of these bulbs is they come up and flower well before the grass starts growing. Careful selection of bulb species and varieties will allow the gardener to produce a burst of color in a lawn area that will return each year. With good plant selection, the bulbs will have done their thing and gone back to sleep by the time the lawn mowers get started.
I just picked up a large number of crocus bulbs to plant in my lawn. I plan to just toss them out and then plant each one where it lands to establish a random cluster of flowers that will emerge late in the winter. I am thinking I will do the same with some snowdrop bulbs for a shady area in the wood at my lawn’s edge.
Enjoy your garden.
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