Question: Many stores and garden centers are offering phalaenopsis orchids so I bought one. How long does it last in the home and what care is needed?
Answer: Keep your new orchid in bright light but out of the direct sun and water to maintain a slightly moist growing median. Usually a once- or twice-a-week watering is all that is needed for this most-durable orchid. Phalaenopsis orchids can remain in bloom for weeks to even months inside the home with good care. After the flowers are gone, remove the stalks where the blooms were present and move the plant outdoors to a shady site. The plants can receive some filtered sun. Keep moist and fertilize every other week with an orchid fertilizer during the spring through fall months. Your plant should bloom again after a period of growth and can be displayed again indoors.
Q. We are trying to establish a native flower backyard and a plant is growing that has been identified as Bidens alba. Should I keep it or let it grow and flower?
A. Better think twice or even three times before establishing this wildflower in your landscape. Yes, it is pretty with white blooms having yellow centers, but it’s also a nuisance, or as some say, invasive plant. Bidens alba is a native plant also known as Spanish needles and beggarticks that spreads quickly throughout landscape. One big problem and reason for the movement is the seeds with two projections that attach to about anything and eventually disperse into the landscape. Plants do provide plenty of pollen for bees and are edible if you want to give them a try. Regretfully, many gardeners have to spend lots of time pulling them from their ornamental plantings.
Q. I removed New Guinea impatiens with root knot nematode damage from a flower bed but the annual periwinkle does not seem to be bothered. Is it resistant to nematodes?
A. Planting annual periwinkle, also known as Madagascar periwinkle and vinca, may be a way to beat some root knot nematodes. This plant can be confused with the true vinca, so make sure we are talking about the annual bedding or container form which has selections with an array of flower colors, the most common being pink and purple. University studies report the annual periwinkle is resistant to some forms of root knot nematode. They also note, if galls develop on the roots the plants continue to grow. So, what you are seeing in your flower bed may be a resistant periwinkle or one tolerant of the nematodes in your soil. Better keep these flowers growing.
Q. The bulbs in the back portion of my amaryllis bed didn’t flower. Should they be replanted?
A. Sounds like bulbs in the back of this bed may be trying to tell you something. It may be as simple as not enough light or maybe staying too dry. Now is a good time to remove all the bulbs and rework the bed. Possibly some other plant may be best for the back of the bed with the bulbs out front. Don’t forget amaryllis plantings do need fertilizer, too, so feed the plantings lightly two to three times a year with a slow-release product found at garden centers.
The Plant Doctor: Add color to flower beds with durable pentas and coleus
Q. Are there any vegetables that should not be planted next to each other? For example, is it alright to plant carrots next to watermelons?
A. The carrots won’t mind the watermelons unless they come creeping into their garden space. Actually these crops are usually planted at different times of the year in Florida so they may never meet in the garden to become entangled. I cannot think of a crop that is going to affect another unless they are crowded or one shades the other. Some vegetables like squash may cross-pollinate but you won’t notice the effects unless you save the seeds and plant them to grow another crop.
Q. I have a large backyard where the Floratam St. Augustine grass is being taken over by what is being called wiregrass. Is there anything that can be done to remove the weedy grass?
A. Common names can be a bit confusing but most often wiregrass is wild bermudagrass. You might drop some samples by your local University of Florida Extension Office to be sure of what is invading your turf. Regretfully most grasses cannot be easily removed from St. Augustine and especially bermudagrass. Now here is your dilemma. Do you just mow it — after all it is green — or do you kill out the patches intermingled with the good grass and resod? If you apply a herbicide, select one that allows sodding after the weedy grass declines. Let the treated areas set a few weeks and keep them moist to see if any more weedy portions sprout and reapply the herbicide as needed. When you are sure the unwanted grass is gone you can remove the debris, till the ground and resod.
Q. A weed called sedge is popping up in our St. Augustine lawn. I have been told to dig or pull it out. Is there anything else to do?
A. You can dig and pull and never seem to get some sedges under control. For those who don’t know this weed it is the greenest, most upright and shiniest looking growth in the lawn. It also resembles grass so it’s important to learn the difference. Sedges produce flower stalks with three sides to the stems to separate them from the grasses. Sedges can be controlled by hand removal but there’s often quite a bit of this weed by the time it’s noted. Many gardeners are looking for an easier route which can be an application of one of several herbicides available at local garden centers labeled specifically for sedge. Make sure your lawn type and type of sedge are listed on the label. Read the labels carefully as these products vary as to best time of application. They’re not always fast acting either, so give them time to remove your sedge.
Tom MacCubbin is an urban horticulturist emeritus with the University of Florida Cooperative Extension Service. Write him: Orlando Sentinel, P.O. Box 2833, Orlando, FL. 32802. Email: TomMac1996@aol.com.
