1. Q. I have some large, healthy hydrangeas that refuse to bloom other than perhaps one large bloom per year. Any ideas on what the trouble might be?
A: Hydrangeas require full sun and adequate moisture for best bloom. If you are meeting these needs, the only other obvious cause of lack of bloom is improperly timed pruning. Prune the plants immediately after bloom, so that new growth will be able to develop flower buds in the fall. Pruning in the spring or early summer removes the fall developed flower buds, preventing bloom for that year.
2. Q: I decided this year in my flower bed to grow Gardenias and Hydrangeas. I currently have Caladiums in this same bed as well as some Texas Salvia (Victoria). Since my Gardenias require acidic fertilizer I am wondering if I should move my Caladiums and and Salvia.
A: Not only do your gardenias and hydrangeas demand acidic soils, they will die if they do not have an acidic soil (pH 5-6 minimum) WHICH ACIDIC FERTILIZER CAN NEVER FULLY FURNISH. You have to use acidic parent material for your growing mix so as decomposition occurs, the plants will consistently have the ideal pH in which to extract minerals and nutrients from. Your soil is so buffered (highly alkaline because of a calcareous parent material) just the addition of an acidic fertilizer will never change the soil and keep the soil pH where it should be. What you should do is excavate a volume of soil from the planting bed and replace it with a mix of two-thirds spaghum peat moss and one-third washed (Builders Sand) sand or potting mix. This mixture can also be used in containers for growing azaleas, gardenias or hydrangeas. Be sure that this planting location receives morning sun and afternoon shade to insure success. The caladiums and Victoria salvia will flourish even better in this situation. You might want to add some Osmocote Slow-release fertilizer pellets (follow label instructions for amount for volume of bed) into this mix before planting begins. Then water with your acid-based water soluble fertilizer such as Miracid, MiracleGrow or Peters 20-20-20 every week.
3. Q: I am bound and determined to get a hydrangea plant to grow on the shady side of my garden under an Angel's Trumpet tree, but I have been unable to keep one healthy. Although it gets some afternoon sun, it does not get any in the morning. I water it every day, but the leaves are getting brown around the edges and it seems to be shrinking away from the sun. I have heard that hydrangeas adapt to sunlight, but am wondering if zone 9 is too hot for them. I have seen several healthy bushes around the neighborhood and need some advise as to what these people might be doing to keep them nice.
A: Hydrangeas do tolerate light shade but if you have it in dense shade it will not bloom well and the growth will be leggy. I think your main problem is overwatering. If the hydrangea is in the soil, watering it everyday IS EXCESSIVE; once weekly, depending on soil type (heavy, clay soil requires much less watering than sandy soil) is plenty. So drop back on the watering. Brown-around-the-edges leaves indicate a root problem -- either too much rotting the roots or too little water drying the roots out -- I bet on the too much water!! Also, when you do water, after a week or 10 days, water with a water soluble fertilizer such as Miracle Grow, Rapid Grow or Peters 20-20-20. Apply this water soluble fertilizer every second or third watering and see if the plant doesn't do better.
3. Q: What kind of fertilizing schedule should I use for my potted hydrangea plants?
A: You should care for your potted hydrangea just as you would any houseplant. Keep the root zone moist -- not wet; not extremely dry. Fertilize once a week by watering with a water soluble fertilize such as Miracle Grow, Rapid Grow or Peters 20-20-20 according to label instructions (how much to put per gallon of water). Keep in the location which receives the most sun possible or if you put it outdoors, find an area which receives morning sun and afternoon shade.
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