Shrubs

1. Q: How do you protect waxleaf ligustrum from possible freeze damage?

Also, live oak, azaleas and Indian Hawthorne?

A: Be sure shrubs are well watered and mulch as much as possible. Leaves piled up over the shrubs roots will help. You can cover with containers or blankets as long as they are removed when the sun comes out. May still be difficult to protect when temperature drops to zero and below.

2. Q: When do you prune photinia?

A: Just before new growth starts in the spring.

3. Q: Indian Hawthorne looks sick; is dropping leaves and has sparse foliage.

What is the problem?

A: The dropping of leaves and sparse foliage are good symptoms of overwatering. Check the root system, for poor drainage, and for compacted soil.

4. Q: When do you prune pittosporum?

A: After the last expected freeze date.

5. Q: Can a yucca plant be cut back to be made fuller?

A: No.

6. Q: Can a potted plumeria be pruned before bringing indoors?

A: Yes. It would be best to prune very little. They should not need much pruning. Done before spring growth is best, but fall is OK.

7. Q: When can you prune hibiscus and bougainvillea?

A: Hibiscus and bougainvillea should be pruned in early fall. If root cuttings are desired, overwinter plant in house or preferably a greenhouse. Can prune in the spring before putting back outside for the summer.

8. Q: When do you prune crepe myrtle?

A: Late January or February. If tree form, prune suckers and seed heads. Cut back to pencil size branches. If a shrub is desired, cut largest limbs to the ground to allow suckers to maintain a shrub.

9. Q: Why are hibiscus leaves turning yellow and falling off?

A: Could be any number of things. Overwatering, underwatering, spider mites, lack of sunlight, or extreme environmental changes assuming it was brought indoors. Check the root system.

10. Q: When do you prune freeze damaged shrubs?

A: Wait until new growth is well established; then prune out only dead areas (if any) or prune for appearance. If the shrub is a spring flowering shrub you should wait until blooms are gone.

11. Q: When is best time to move crepe myrtle?

A: Fall or during the dormant season.

12. Q: How and when do you prune nandinas?

A: Remove one-third of old canes all the way to the ground. Can be done anytime now.

13. Q: When should Chinese holly be pruned?

A: Generally after the last expected freeze date. May need to prune several times during the growing season to keep shape.

14. Q: Request for a recommended shrub that will serve as a wind break.

A: Recommended junipers, hollies.

15. Q: Is a photinia subject to fire blight?

A: Yes. May have twig dieback if the shrub is not in full sun most of the day.

16. Q: How do you start a flowering quince?

A: Softwood cuttings in the spring or hardwood cuttings in the fall.

17. Q: Request for information on the dangers of Carolina jessamine.

A: All parts of the plant are extremely poisonous. Homeowners should use caution depending on their individual situation; i.e. accessibility to children and pets.

18. Q: Is there a nandina variety that grows to 28 inches?

A: Consider Gulf Stream

19. Q: What type of shrub can be used in a 3 foot wide strip between a fence and a sidewalk that is in semi-shade?

A: Nandina. Select variety based on height desired.

20. Q: How do you prune oleanders?

A: Normally oleanders should not be pruned. Their natural growth pattern is multi-trunk with blooms on the terminal ends. It may be necessary to remove branches that die back. These should be removed at ground level.

21. Q: What is a good ground cover, shrub or flower for a strip 25 inches wide and 25 feet long by a driveway that gets west sun?

A: Shrubs: Dwarf nandina, dwarf yaupon holly

Ground cover: Liriope, mondo grass

22. Q: Can dwarf nandina that is too tall and thick be pruned?

A: Yes, by removing selected canes all the way to the ground.

23. Q: What fertilizer should be used for crepe myrtle?

A: Suggest one with a 3-1-2 or 4-1-2 ratio.

24. Q: What do you spray on pyracantha for fire blight?

A: Streptomycin or Agri-Step

25. Q: Can you transplant a yucca?

A: Probably not successfully. Has a very deep tap root, deeper than the plant is tall.

26. Q: Request for shrubs to replace ligustrum that can be maintained in a formal shape with maximum height of 4 feet with a glossy green look.

A: Hollies. Dwarf Burford Holly best meets specs.

27. Q: What caused Burford Holly to die? Burford holly dying from ground up; has black/brown crispy leaves.

A: Overwatering is most common cause of Burford holly dying.

28. Q: What is spacing for planting althea and Dwarf Burford Holly?

A: Mature spread of Althea is 3 to 5 feet, plant on 2 foot centers. Dwarf Burford holly spread is 3 to 4 feet, plant on 18 inch centers.

29. Q: Why doesn't my wisteria bloom?

A: Possibilities: Too much shade, wisteria requires full sun; too much nitrogen (may be located in or too close to lawn); too much moisture causing plant to produce only leaves; pruning during fall or winter (wisteria set buds in fall for next spring blooms - prune immediately following blooming season).

30. Q. Does it matter where I prune the branches on my shrubs and roses?

A. When pruning twigs and small branches, always cut back to a vigorous bud or an intersecting branch. When cutting back to a bud, choose a bud that is pointing in the direction you wish the new growth to occur. Be sure not to leave a stub over the bud or cut too close to the bud.

When cutting back to an intersecting (lateral) branch, choose a branch that forms an angle of no more than 45 degrees with the branch to be removed. Also, the branch that you cut back to should have a diameter of at least one-half that of the branch to be removed.

Make slanting cuts when removing limbs that grow upward; this prevents water from collecting in the cut and expedites healing.

31. Q: I have a Loquat Shrub some 3 feet high grown from a fruit brought in Spain as a Nisperro. Will it survive an English Winter? It is outdoors in summer and in a Glasshouse in winter.

A: The plants themselves will be killed to the ground if temperatures below 20 degrees F occur. Many times the roots will resprout. If the ground freezes, it should kill the loquat. Moving it in and out would be your best chance for fruiting and tree survival if you are not in a semi-tropical area.

32. Q: I am planning to buy a tree peony and grow it in a large container. I am unsure how to proceed this winter. Do peonies have a cold requirement? How cold can they stand? I can keep the tree in the garage, where it is slightly warmer and with obviously less wind chill. What do you recommend? Also, do you know the answer to the same question regarding lilacs?

A: We don't grow peonies in Texas so I had to consult with some of my Northern experts to find some answers for you. The peony and lilac need cold exposure to bloom normally. I could not find out how cold the plant could withstand but I imagine since they are grown in the north, both plants could withstand 10 degrees F. or lower. When peonies are "forced" (caused to bloom early), they are planted outside until February or March then dug and brought into the greenhouse. Your idea of keeping it in the garage is a good idea especially since I do not know if peonies are root hardy (some plant's root system are less hardy - can survive less cold - than the tops -- holly being an example.

33. Q: I have a Turk's Cap and Red Mallow plant seperated by about 15ft. I would like to establish a larger grouping to entice more hummingbirds. Do you take cuttings...dig and seperate roots?

A: Turk's Cap can be propagated from seed (planted directly out of the red fruit) or from cuttings. Cuttings root rather easily (2-3 weeks under mist) if young wood is used. I guess you could layer stems (bend over and bury a portion of the stem leaving it connected to the Mother plant and the growing point of the stem sticking out of the soil) in about 3-4 weeks. Scar the buried section with a knife on both sides before burying. Turk's cap should be readily available in local nurseries.

34. Q: I have a tiled patio and would dearly love to have a Wisteria trained over the patio doors. My only problem is that it would have to be planted in a container. Are any varieties of Wisteria suitable for this purpose?

A: Remember that anything can be grown in a container that can be grown in the ground IF you remember that soil in a container turns to brick. Now, with that out of the way, simply get a large, whiskey barrel (20 or 30 gallon container), fill it with potting mix or a planting mix as close to 1/3 soil, 1/3 sand and 1/3 organic matter or mulch as possible. Add some slow release fertilizer pellets or rotted manure and fertilize with a water soluble fertilizer every two weeks. MAKE SURE the container selected drains well and won't rot the plant's roots. Choose the wisteria of your liking and get ready for a twining, blooming beauty for years to come.

35. Q: I received a true Bay Tree and would like some information on suggested pruning & care. It is now 2 feet tall. The trunk is 1 foot and it has 2 lateral branches that are each 1 foot tall and stick straight up. The tree looks like a Y. I would like to plant it in my herb garden this spring/summer and would like to know how tall it will get, if it will produce any suckers or water spouts(and should these be removed?), any pests,and what is the desired shape?

A: There is a Bay-tree or Sweet Bay which are common names for the genus Laurus (Laurel), evergreen shrubs or trees with long, oval glossy green leaves. The name Sweetbay is also given to Magnolia glauca, a shrubby tree native from Mass. to Fla. and Texas. However, if you are talking about the Bay Live Oak, Q. virginiana var. maritima, the one used in cooking, it is a shrub, or smaller tree. It is a low maintenance tree since it is found in sandy soil, usually near the coast. In Florida it is not only found on the coastal sand dunes but also in the scrub lands of the central part of the peninsula. Since both of these bay trees are described as shrubs, I would suggest you prune them as such. If you want to take a fork out of the plant, do so. It may make it sprout from the ground into a shrub form. I would recommend mulch around the base 2-3 inches deep in a three foot donut around the plant. Keep moist but not wet. Prune to keep a shrubby appearance. The plant should be relatively pest free. Fertilize in the spring (February) with a fertilizer containing at least 50% slow release nitrogen (such as 19-5-9).

36. Q: I recently saw a lovely little tree with yellow blossoms, which were identified to me as belonging to a cassia tree. Can you tell me anything about its growth habits, needs, deficiencies, etc?

A: Cassia is a genus (of about 400 species) of herbs, shrubs and trees native in tropical and temperate regions, belonging to the Pea Family. I imagine the Cassia you are describing is Cassia alata or the Candletree. It grows in full sun or light afternoon shade. It grows to 5 to 8 feet tall. It produces rich, buttery yellow candelabra-like flowers from late summer well into the fall. It has attractive tropical-looking foliage on tree-form plants. It is an excellent background plant behind copper plants and other tall summer and fall color annuals. It can be planted singly, or massed. Try to find nursery transplants in the spring. Because of its rapid growth, they will need regular watering and monthly feeding with a complete-and-balanced plant food. Of course, they are tropical and will freeze with the lightest frost. They thrive in any soil type if prepared with lots of organic matter and prefertilized with 3 pounds of the complete and balanced fertilizer per 100 square feet of bed.



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