Strategies to Control Loropetalum Decline in Central Florida1

Strategies to Control Loropetalum Decline in Central 

Florida 1 

Amy L. Shober and Gary L. Leibee 2 

Introduction 

Loropetalum chinensis (also called Chinese 

fringebush or Chinese witch hazel) is a woody 

ornamental plant that is commonly used in the 

landscape in Florida. Loropetalum is native of China, 

Japan and the Himalayas and comes in several 

cultivars with variable foliage and flower color. The 

cultivar Ruby has been a popular choice in Florida 

landscapes because, in addition to its attractive 

burgundy foliage and beautiful pink flowers, the 

Ruby cultivar grows to 4-6 ft high and wide 

compared to an average 8-10 ft for other cultivars 

(Fig. 1). 

Loropetalum 'Ruby' has long been considered a 

fairly low maintenance landscape plant with few 

insect or disease problems. However, in recent years, 

there have been increasing reports and complaints of 

unexplained decline, especially in central Florida. 

The most commonly reported symptoms of decline 

include new growth that is stunted or deformed (Fig. 

2), curling of leaves, defoliation (Fig. 3), and in 

extreme cases, plant death. Possible explanations for 

Loropetalum decline include eriophyid mites, nutrient 

Figure 1. Healthy Loropetalum 'Ruby' plant. 

SL 255 

deficiency (especially micronutrients), root rot, 

nematodes and salt toxicity. 

Soil and tissue sample analysis from several 

areas in Orange County experiencing Loropetalum 

decline suggested a potential micronutrient 

deficiency (Cu, Zn, Mn, or B) or eriophyid mite 

infestation. In order to identify possible causes of 

1. This document is SL 255 one of a series of the Soil and Water Science Department, Florida Cooperative Extension Service, Institute of Food and 

Agricultural Sciences, University of Florida. Original publication date October 2007. Visit the EDIS Web Site at http://edis.ifas.ufl.edu. 

2. Amy L. Shober, assistant professor, Gulf Coast Research and Education Center; and Gary L. Leibee, associate professor, Mid-Florida Research and 

Education Center. Florida Cooperative Extension Service, University of Florida, IFAS, Gainesville, FL 32611. 

The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and 

other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, 

sexual orientation, marital status, national origin, political opinions or affiliations. U.S. Department of Agriculture, Cooperative Extension Service, 

University of Florida, IFAS, Florida A. & M. University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Larry 

Arrington, Dean

Strategies to Control Loropetalum Decline in Central Florida 2 

Figure 2. Stunted and deformed new growth on 

Loropetalum 'Ruby' in a commercial landscape in Orange 

County, FL. 

Figure 3. Severe defoliation of Loropetalum 'Ruby' plants 

from a residential median area in Orange County, FL. 

decline and develop management methods to control 

plant decline, two research studies were conducted. 

The first study was conducted at the Mid-Florida 

Research and Education Center (MREC) in Apopka, 

FL. This study evaluated the use of a carbaryl 

miticide (Sevin) and several foliar fertilizer 

treatments (Table 1) on Loropetalum growth and 

plant quality using 180 potted plants showing 

symptoms of decline. The fertilizer treatments 

included Cu (as copper sulfate pentahydrate) at a high 

and low rate, Cu (as Kocide 2000) at the label rate, 

Mn (as manganese sulfate), Zn (as zinc sulfate), B 

(as sodium pentaborate – Borax), and Peters 

S.T.E.M. at the high label rate. All sulfate solutions 

were mixed with hydrated lime to adjust pH. There 

was also an untreated control for a total of eight 

fertilizer treatments. Each fertilizer treatment was 

applied once to 18 individual plants, where nine of 

those plants were treated with the carbaryl miticide 

monthly and nine received no miticide. 

Results indicated that there were no significant 

effects of miticide or foliar fertilizer on plant growth 

(height x width x breadth) at any time during the two 

month evaluation. There was, however, a significant 

fertilizer treatment effect on plant quality evaluated at 

3 and 7 weeks after treatment (Table 2). Plants 

sprayed with the foliar Cu treatments tended to be the 

healthiest with slight to no mite damage and good to 

fair (sellable) plant quality (Fig. 4). The quality of 

the Cu treated plants was always significantly better 

than the untreated plants, and in many cases better 

than plants sprayed with B or Peters STEM. In all 

cases, the use of Sevin miticide did not affect the 

performance of any foliar fertilizers. However, a 

decline in plant quality at 12 weeks after treatment 

suggests that the effects of the foliar fertilizers will 

decrease with time. 

An additional study was conducted at the Gulf 

Coast REC in Wimauma, FL to evaluate the potential 

for amending soil with Cu to prevent decline of 

Loropetalum Ruby. Soils were amended with copper 

sulfate (CuSO 4 •5H 2 O) at 0, 2.5, 6.25and 10 lbs Cu 

ac -1 or with a micronutrient mix (5 lb fertilizer 1000 

ft -2 ). However, at 16 weeks after treatment there is 

no evidence that soil Cu fertilization has had any 

effect on plant growth (height x width x breadth), 

quality or density. 

Figure 4. Comparison of Loropetalum 'Ruby' quality 

between plants receiving no foliar copper fertilizer (left) and 

plants receiving the high copper sulfate/hydrated lime foliar 

fertilizer treatment (right). Photo was taken ten weeks after 

fertilizer and miticide treatments were applied.


Recommendations 

We currently recommend planting 'Burgundy', 

'Plum', or another cultivar with similar 

characteristics (e.g., red/purple new growth, pink 

flowers) to 'Ruby', since there have been no reports 

of widespread decline for these cultivars in Florida. 

The following tips will help you to identify different 

cultivars. Loropetalum 'Ruby' is a small (3-5 ft tall), 

rounded plant with leaves that are more rounded and 

pink flowers that bloom year round (Fig. 5). 

Loropetalum 'Burgundy' (also called 'Sizzling Pink') 

will stand more upright than 'Ruby' and grows to be 

6-10 ft tall. Loropetalum 'Burgundy' has elongated, 

pointed leaves that turn bright red in the fall and 

flowers that bloom intermittently (Fig. 6). 

Figure 5. Loropetalullm 'Ruby' has smaller more rounded 

leaves and pink flowers that bloom year round. 

Figure 6. Loropetalum 'Burgundy' (also called 'Sizzling 

Pink') has elongated, pointed leaves and flowers that 

bloom intermittently 

Loropetalum 'Plum' (also known as 'Hines 

Purpleleaf', 'Plum Delight' or 'Pizzazz') has dark 

foliage and tends to have smaller, darker flowers (Fig. 

7). This cultivar will grow to be 6-8 ft tall. While 

other cultivars tend to grow larger than 'Ruby', 

proper pruning will help to maintain them at a smaller 

size. Figure 7. Loropetalum 'Plum' (also known as 'Hines 

For existing plantings of Loropetalum Ruby, our 

research results suggest that quarterly foliar 

applications of Cu could improve plant quality in the 

landscape. The amount of Cu to apply will vary 

based on the source of Cu that will be applied. This is 

because the plant availability of Cu is dependent on 

the efficiency of the active Cu compound to release 

Cu 2+ which occurs roughly in the following order: 

copper sulfate pentahydrate (no lime additions) > 

Purpleleaf'. 'Plum Delight' or 'Pizzazz') has dark foliage 

withsmaller, darker flowers. 

copper hydroxide > copper tallate copper ammonium 

complex tribasic copper sulfate. 

For best results, we suggest application of a 

5-2.5-100 Cu/lime mixture. To create this mixture, 

add 5 lbs powdered copper sulfate pentahydate and 

2.5 lbs fresh hydrated lime to 100 gallons of water.


Spray each individual plant thoroughly. Remember 

that several common fungicides utilize Cu hydroxide 

(Cu(OH) 2 ) as the active ingredient (e.g., Kocide 

2000, Champion WP, Agri Star Nu Cop). If you are 

already treating Loropetalum for a fungal pest, you 

will not need to apply an additional source of Cu to 

control decline. 

When using any foliar Cu treatment, avoid 

spraying surrounding plants as phytotoxicity may 

occur. These materials can also cause damage to 

metal surfaces such as cars, lawn furniture, etc. In 

addition, applicators should wear appropriate 

personal protective equipment when applying foliar 

Cu sprays.


Table 1. Concentrations of trace elements applied foliarly to each plant in 250 mL of solution. 

Treatment Cu Zn Mn B Mo Fe 

mg 

CuSo4 - Low 158 0.0 0.0 0.0 0.0 0.0 

CuSo4 - High 318 0.0 0.0 0.0 0.0 0.0 

Kocide 2000 1575 0.0 0.0 0.0 0.0 0.0 

MnSO4 0.0 0.0 185 0.0 0.0 0.0 

ZnSO4 0.0 328 0.0 0.0 0.0 0.0 

Borax 0.0 0.0 0.0 22.0 0.0 0.0 

Peters STEM 4.8 6.8 12.0 2.0 0.1 11.3 

Control 0.0 0.0 0.0 0.0. 0.0. 0.0. 

Table 2. Loropetalum plant quality ratings at 2 and 4 weeks after receiving fertilizer and miticide treatments. Values with the 

same letter are not statistically different. Plant quality ratings were as follows: 1 = good; 2 = fair; 3 = moderate; 4 = poor; 5 = 

very poor. 

Fertilizer Treatment 2 weeks after 

treatment 

Quality 

4 weeks after 

treatment 

CuSO4 - Low 1.6 a 1.8 ab 

CuSO4 - High 1.3 a 1.6 a 

Kocide 2000 1.2 a 1.7 a 

MnSO4 3.1 b 2.8 bc 

ZnSO4 2.8 b 2.5 bc 

Borax 3.2 bc 3.4 cd 

Peters STEM 3.5 bc 3.2 cd 

Control 4.1 c 3.4 cd

Strategies to Control Loropetalum Decline in Central Florida1

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