May 5, 2016 – Kenosha News
Question: I planted daffodils at least twelve years ago. They bloomed beautifully for two years. Since then, nothing but greens. To my amazement, they have bloomed this spring! Why is that? L.P.
Answer: I think your daffodil bulbs may have been planted too shallowly. Daffodils should be planted 7 to 8 inches deep. Daffodils and tulips can reproduce themselves by developing smaller bulblets around the original bulb. The shallower the bulbs are planted, the greater the chance the original or mother bulb will develop bulblets. Over time the mother bulb gets smaller – too small to produce flowers – as the energy goes into the daughter bulblets. The daughter bulbs produce leaves only until they reach sufficient size.
Twelve years is a long time for the bulblets to grow large enough to bloom so there may have been other factors slowing growth and development of your daffodils. Bulbs require a large amount of carbohydrates (sugars and starches) to develop flowers – much more than needed to produce leaves. Plants produce sugar through photosynthesis. If you remember grade school science, photosynthesis is carried out by chloroplasts in the green leaves. After sugar is produced in the leaves it is transported via the vascular system into the bulb to keep for future use (i.e. next year’s flowers and leaves). Bulbs in part sun or shade have less sunlight so can’t make as many carbohydrates and may bloom less. Removing, braiding or folding the leaves before they finish their job, which is indicated by turning yellow, reduces the amount of carbohydrates stored and reduces flowering.
You might check the depth of your daffodils. If they are shallow, dig them up after the leaves turn yellow. Cut off the dead leaves and store the bulbs in a dark, cool, dry place. Replant 7 to 8 inches deep in fall.
Question: I’d like to use old railroad ties for a raised bed. They are old, washed grey ties. Do you think the preservative has leached out of them and made them “safe” for garden production? D.M.
Answer: The creosote used to treat railroad ties is toxic to plants. It leaches into the soil and inhibits plant growth. I checked references from the University of Minnesota and University of Missouri. The consensus is in old, weathered railroad ties most of the creosote has leached out and the ties are okay to use for raised beds. The only way to find out is to try and see if plants thrive.
Barb Larson is horticulture educator for the Kenosha County University of Wisconsin Extension. She holds a master’s of science in horticulture from the University of Wisconsin-Madison. If you have a plant or gardening question, email her at firstname.lastname@example.org or call 262-857-1942.