Answer: It's either a boron or calcium deficiency, says Tim Peters, research director at Territorial Seed Company in Cottage Grove, Oregon. Hollow centers in cucumbers and melons and hollow stems in brassicas are common in our area and are caused by low levels of these elements in our soil, explains Peters. And even if levels are adequate, fluctuating moisture conditions or excessive nitrogen fertilization can cause a deficiency to occur, he adds. Test the soil to determine if you have a boron or calciumdeficiency. Add Borax for boron deficiency and bonemeal for calcium deficiency, recommends Peters. Don't overdo it though: in general, the amount of boron to add is minute, on the order of one teaspoon in five gallons of water sprinkled over 100 feet of row. With bonemeal you would add much more, about five pounds hoed into 100 feet of row. Mixing either element with compost or manure will help to stabilize it in the soil, preventing leaching. If a soil test indicates adequate levels of these elements in the soil, try to reduce the amount of nitrogen you apply, and mulch your crops with a three to four inch deep layer of jay or straw to prevent moisture fluctuations. Also, some cucumber varieties are less susceptible to hollow centers than others. For our area, try growing SMR 58 and Cascade, say Peters.
Q&A Library Searching Tips