What makes a rhododendron a healthy, reliable bloomer?

Richard writes: Last year we had fewer flower buds on our rhododendron. It has bloomed faithfully in the past. What is causing a reduction in the bloom?

There are several reasons for bloom failure/reduction in the amount of seasonal bloom. After evaluating your plant’s growing conditions, determine if one of the following reasons could be the cause.

Failure to remove previous year’s bloom. A plant has put all of its energy into seed production instead of producing blooms.

Failure to deadhead leads to heavy blooming every other year with few or no blooms in-between.

Over fertilizing with high nitrogen produces vegetative growth. Cut back on nitrogen but maintain phosphorous and potassium for good flower production.

Deep shade from nearby trees that have grown taller and wider. This can cause low bloom in older plants. Light is required for bloom but not so intense that is causes the leaves to sunburn.

Lois writes: I am searching for a large deciduous shade tree with a deep root structure that can be planted in a hot and dry southern exposure area of our garden. We have a large piece of property so we can handle a good-sized shade tree. Oak root fungus has been a problem in our development, so I have been advised to only plant trees that are resistant to the fungus. As a result, the tree selection process has us stymied. Help!

The common hackberry, Celtis occidentalis would be an excellent choice. It fulfills your criteria plus it has several winning attributes.

Berry-like fruist attract birds, easy care with little to no pruning required, tolerates alkaline soil, and has yellow leaves in the fall. It is slower in growth than other shade trees because it does not leaf out until mid-spring. Therefore, don’t be alarmed about the slow emergence of leaves and think the tree is dying.

Even though it will thrive in your sunny exposure, you will still need to be diligent about watering and mulching until the tree becomes established and thriving.

A slow drip of water three times per week should be sufficient while it is becoming established. If your soil is a heavier clay perhaps, twice a week will be sufficient. Sandy loam usually takes more water. Mulch should be kept away from the base of the tree and should be at least 3 inches deep.

Sonny asks: We have recently relocated to a condominium with little to none space available to garden outside. I have decided to focus on interesting houseplants instead. Fortunately there is plenty of natural light in our condominium. The plant that intrigues me is the shrimp plant. What can you advise me about its growing requirements?

The shrimp plant is botanically known as Beloperone guttata. It is an easy to grow, flowering houseplant that bears unusual salmon-colored shrimp-shaped flower heads at the end of arching stems with a downy texture. Small white flowers protrude at the ends of 4-inch-long shrimp-like bracts.

It will bloom almost year round, prefers warm day temperatures and cooler nights during the winter months. Place in an area that receives very bright sun for best performance.

Water liberally spring through autumn and sparingly in winter. But don’t let it sit in standing water (as with all house plants). During the winter mist the leaves to supply some humidity. Cut back the plant to half size each spring, and if needed, it may be repotted at that time.

Try combining a group of semi-colored foliage plants such as Begonia rex. Rex begonias prefer drier soil and an indirect to shady exposure. Repot begonias in spring, and it is easily propagated by leaf cuttings. Tip: rex begonias will lose their vibrant colors if pot bound. So, repotting is necessary when you see a loss of foliage color.

Janice T. of Santa Rosa asks: I would like to add to my collection of spring bulbs by planting something other than daffodils and tulips. Can you suggest a few that are different and unusual?

Here are a few that would add beauty to anyone’s garden. Allium-?Flowering onion, Anenome-Windflower, Chionodoxa-Glory of the snow, Colchicum-Colchicum, Fritallaria-Fritallary, Hyacinthoides- English Bluebells, Ipheon- Spring starflower, Leucojum- Summer snowflake, Lycoris- Spider lily, Scilla- Siberian Squill.

Shelly U. from Windsor asks: I still have quite a few eggplants that are not quite ready to be picked. Can I pick them even though they are still small and immature?

If your plants are dying down, or there’s the threat of frost coming, don’t hesitate to pick whatever eggplants are still on the plants. As long as they are about a third of what their mature size should be, then they’ll be good to eat. Don’t bother picking the very small ones.

Dana Lozano and Gwen Kilchherr are garden consultants. Send your gardening questions to The Garden Doctors, at pdgardendoctor@gmail.com. The Garden Doctors can answer questions only through their column, which appears twice a month in the newspaper and online at pressdemocrat.com