The following questions have been asked during the Master Gardener Call-in Gardening Show on KONP that airs on the last Monday of each month from 1-2 p.m.:
Question: My father used to put ashes from our fireplace on our vegetable garden. Should I do this, too?
Wood ash is a homemade source of potassium, phosphorus, calcium and boron, nutrients needed by all plants in differing amounts.
Because local soils typically have sufficient levels of these nutrients, applications of wood ash usually are not needed. But since wood ash is also very alkaline, it can be used to raise the pH of the soil.
pH is a measure of acidity that goes from 1 to 14. A measurement of 7 (right in the middle) is considered neutral; a pH of less than 7 is acidic (with the lower the number the more acidic the substance); a pH of greater than 7 is alkaline (with the higher the number, the more alkaline.)
If your soil is more acidic than desirable for the crop you are growing, scatter wood ashes lightly on the soil surface. Don’t leave the ashes in piles or clumps. Keep ashes away from foliage, especially that of young seedlings.
Do not use wood ashes if your soil has a pH of 7 or higher. Do not use wood ashes around acid-loving plants such as blueberries, rhododendrons and azaleas. Do not use wood ashes on potatoes because they are more likely to get scab disease if the pH is too high. Don’t use ash from treated wood or from burning trash because it may contain chemicals that are toxic to plants.
Question: I can’t grow radishes. I have tried several times and even planted different varieties. They come up nicely but even after 6 weeks of growth, they are all tops and no radishes. What am I doing wrong?
Large luscious radish greens and no harvestable root can result from too much fertilizer. Radishes are light feeders and rarely need supplemental fertilizer.
Other reasons for poor root development include planting the seeds too close together, too much shade and planting during the heat of summer.
If addressing the above problems does not do the trick, all is not lost. Consider eating the greens. The texture can be too rough for salads, but they can be used in soups or as cooked greens and work beautifully in pesto.
Question: My sweet cherry tree is oozing a sticky, jelly-like substance from the trunk. What is it?
Sticky sap oozing from a cherry tree (sometimes called gummosis) usually is a sign of stress. It can result from a number of causes including unfavorable growing conditions, sunscald and mechanical injuries (such as from a lawn mower or weed whacker). Gummosis also can be caused by insects boring into the soft inner wood.
Unfortunately, gummosis on cherry trees often is caused by a bacterial or fungal infection. In these instances, the oozing usually is associated with a canker (a dark, sunken area of dead bark and wood). The canker usually increases in size over time, often girdling the affected twigs and branches, causing dieback above the lesion.
Fungal and bacterial cankers are difficult to control particularly when they occur on main branches or the tree trunk. If caught early, you can prune out the affected branches. Make cuts well below the visible canker and sterilize tools frequently. Do not remove cankers at the same time as regular pruning. Destroy pruned material; do not compost.
Some fungal and bacterial causes of gummosis can be controlled with chemical sprays. The product and timing of applications depend on the specific disease.
Because these diseases can be spread by wind, rain and insects, sometimes the best option is to remove an affected tree to prevent other trees from becoming infected.
Have more questions? Visit a Clallam County Master Gardener Plant Clinic for gardening advice and help with garden problems. Plant Clinics are held on Mondays at the Clallam County Courthouse in Port Angeles from 9:30 a.m. to 12:30 p.m. Plant Clinics will occur on Saturdays at the Master Gardener Demonstration Garden in Sequim starting in May.
Jeanette Stehr-Green is a WSU-certified Clallam County Master Gardener.