Answer: Amaryllis can be grown in water and pebbles for the flowering season, but I don't recommend it if you are going to keep the Amaryllis from year to year. No doubt, an Amaryllis in pebbles, marbles or glass rocks looks really dramatic in a glass container for a short period of time. In addition, often an Amaryllis will develop a better root system more quickly in water than it will in soil. But there is danger of rotting, especially when the Amaryllis is just starting. Also, after a while, the stones get covered in algae and don't look very attractive. Finally, water lacks the nutrients that are in soil.

If you want to try the water and stones method, after the Amaryllis blooms, I recommend you carefully repot it in professional growing mix. Try not to break any roots. If some stones cling to the roots, this is ok. Just repot them along with the Amaryllis, rather than trying to poke them out.

While the Amaryllis is in water, be very careful with the fertilizer. Organic fertilizers may become foul smelling (in which case you need to change the water) and chemical fertilizers may burn the roots if used at full strength.

Question: I have a question maybe you can answer either now or on your radio show, I listen every week. I have a Christmas cactus that has some kind of disease, where the leaves hook to one another there is this white sticky stuff. And where it is back closer to the main stalk, it then falls off. The leaves look good and all of a sudden it will just fall off. And it hasn't bloomed in a couple of years. It’s an old plant and is pretty big, but I'm afraid this year I will lose the whole thing. I hope you can help me.

Answer: I suspect your Christmas cactus has mealy bugs, insects that look like puffs of white cotton. It may also have other problems, but you need to get the mealy bugs addressed first. I suggest removing as much soil as possible and re-potting in a new pot because mealy bug eggs are probably in the soil. I have had the best results taking the plants outside and spraying with Orthene on a warm day. Be sure to spray to the dripping point, so the insecticide covers the entire surface of the plant. If you were unable to do the re-potting, check the pot (including the underside) for mealy bug egg masses--which may be wiped away. Then, when spraying the plant, also spray the soil surface and the entire pot. If you must spray indoors use an insecticide containing pyrethrin.

Mealy bugs are hard to get rid of and spread from plant to plant, so be sure to isolate your Christmas cactus. If any stray mealy bugs reappear, touch each one with a Q-tip dipped in rubbing alcohol. And check all of your plants weekly. Several months of diligent inspection (and touching up with the Q-tip dipped in alcohol) will be needed.

Question: Can you tell me anything about Neem oil for roses? I just read that this is a very good product for roses. Do you sell this product?? If not, do you know where I can get Neem oil? Thank you for your assistance.

Answer: We do sell Neem Oil at Carroll Gardens. Customers are using it with mixed results. They get reasonably good results as a curative insecticide for many insects that trouble roses. They are reporting reasonably good results using Neem oil as a preventive fungicide, but not such good results as a curative fungicide (once the fungus outbreak has occurred). I have found that Neem works better on powdery mildew than on black spot. Incidentally, Neem is reported to be a good preventive for Japanese beetle damage. Personally I have had no such success.

Although Neem is an organic, I have personal concerns about its safety for humans. These concerns are not based on any scientific study but just upon a suspicion. So if you use the Neem oil I encourage you to be cautious.

Question: I have a lawn of Zoysia grass in full sun which has been in place for at least 10 years. It has developed some brown areas. I'm sure there is considerable thatch build up which needs to be addressed. I have a Mantis cultivator with a de-thatching attachment. Will this work, or will I need to apply some other method? Also, what is the best fertilizer to use? I've been told that Zoysia grass needs something with a high nitrogen content. Thank you.

The following are the care instructions for Hydrangea Endless Summer directly from Bailey’s Nursery whom introduced the plant. I thought they were quite good and did not edit them:

Caring For Your Endless Summer® Hydrangea

Thank you for purchasing Endless Summer® Hydrangea. Now that you have the first Hydrangea that blooms on new growth with the ability to rebloom all summer long, here are some tips to make Endless Summer® the center of attraction in your yard.

Northern Climate Winter Care

To ensure overwintering success in the first year, the following is recommended:

* Stop all applications of fertilizer after August 15th to acclimate the plant for winter.

* Keep the soil moist through the fall months until the ground is frozen.

* Cover the plant with a four-inch layer of organic mulch (wood mulch, leaves, etc.). There is no need to cover all stems to the tip or to cut them back.

* Covering should be done when fully dormant (around November 30th), or at the same time you would cover perennials in your garden.

* In spring uncover with your perennials when the ground is no longer frozen. The plant will grow from the base of the plant and also from any old branches that survived winter.

* Be patient. Growth will come slowly until the heat of late spring stimulates the plant to grow faster.

* Once you see growth you can prune back the old branches to a finger width above the new green growth.

* Sit back and watch your plant grow and bloom, which depending on your climate should be some time around the middle of July.

Pruning

Endless Summer® Hydrangea is very forgiving and will not suffer if left unpruned or pruned at the wrong time. In fact, young, recently planted shrubs are best left alone. Unlike other Hydrangeas, your Endless Summer® will bloom on both old and new wood, branches that grew last year and the new branches from this year. Another unique feature is that this hydrangea will continue to set buds and bloom throughout the season; deadheading the spent flowers will encourage this. Feel free to cut the blooms for drying or fresh cut in vases because you will actually encourage the plant to produce more blossoms.

Spring is the best time to prune. Many people like to leave the spent blooms on their plant because it adds winter interest. It may also act to insulate the new buds from frost and cold. They should be removed in spring however.

Changing Flower Color

To encourage flowering, we recommend a fertilizer low in nitrogen and high in phosphorus, with a number over 30. For instance an N-P-K ratio of 10-40-10 would be ideal.

Big leaf hydrangeas are unique in that their flowers can change color. The color of hydrangea blossoms depends on the soil's pH and its ability to absorb aluminum at different levels. An alkaline soil produces pink colors. An acid soil produces blue flowers. You can buy a soil pH testing kit to test your soil.

It is possible to manipulate the color of hydrangeas, but one word of caution:

Many people have killed their plants by applying too much aluminum sulfate.

More is not better.

Changing to pink

To change from blue to pink you need to change from an acid soil to an alkaline one.

* To help raise your pH you can use dolomite lime several times a year. You will have to retest your soil and aim for a pH of about 6.0 to 6.2. If it goes above 6.4, your hydrangea may experience an iron deficiency.

* Use fertilizers with high levels of phosphorus. Phosphorus helps to prevent aluminum from being taken up in the plant's system.

* Consider growing them in a large pot where it is easier to control the pH.

Changing to blue

Lowering the pH of your soil will produce blue flowers with a pH level of about 5.2-5.5. Using a soil acidifier will lower your soils pH for beautiful blue blooms.

Tips for success:

* Ask the Garden Center where you purchased your plants for what’s recommended to acidify the soil in your area. (Note: at Carroll Gardens we recommend aluminum sulphate).

* Follow directions carefully on the product you purchase.

* Thoroughly water the plant before adding any acidifier.

* Adding large amounts of organic matter, such as peat moss and compost-ed leaves, will acidify the soil as they break down.

Remember to check the pH of your water. If you are trying to turn your flowers blue and you have hard water, it will be difficult to achieve. Also remember that concrete foundations and walkways tend to leach lime, raising the pH in that area.