Overview of Rambutan
Phenology, Flowering,
and Fruit Set in Hawai’i
A.M. Kawabata
M.A. Nagao
D.F. Aoki
K.Y. Hara
L.K. Pena
Chanthaburi, Thailand
100
Temperature (°F)
80
60
Monsoon season
Hurricane season
40
Hilo Max
20
Hilo Min
Chanthaburi Max
Chanthaburi Min
0
Jan Feb Mar Apr May Jun
Jul Aug Sep Oct Nov Dec
Month
Chanthaburi Rainfall
25
Hilo
Chanthaburi
Precipitation (in)
20
15
10
5
Monsoon season
Hurricane season
0
Jan Feb Mar Apr May Jun
Jul Aug Sep Oct Nov Dec
Month
Cairns, Australia
100
Temperature (°F)
80
60
-one season
Cycl-
Hurricane season
40
20
Hilo Max
Hilo Min
Cairns Max
Cairns Min
0
Jan Feb Mar Apr May Jun
Jul Aug Sep Oct Nov Dec
Month
Cairns Rainfall
20
Precipitation (in)
16
-one season
CyclHurricane season
12
8
4
Hilo
Cairns
0
Jan Feb Mar Apr May Jun
Jul Aug Sep Oct Nov Dec
Month
Comparisons
Chanthaburi
Cairns
Hawai’i
Flowering Seasons
October to December
July to August; December
to January; thru April
July to August; thru Nov.;
March to May;
No. of Flowering
Seasons
1
1; extended
2
Flushing Seasons
Oct. to Dec.; Sept. (after
harvest), May (monsoon)
Nov. to Dec.; Feb. to
March (after harvest);
May; Jul. to Aug.
Aug. to Sept.; May to
June (after harvest); Oct.
No. of Flushing
Seasons
2; maybe 3
4 to 5
3 to 4
Harvesting Seasons
February to June
December to January;
thru March; thru August
Dec. to Jan.; thru Mar.;
Aug. to Sept.; thru Oct.
No. of Harvesting
Seasons
1
1; extended
2
Flowering in Hawai’i
•
•
•
•
•
Response to water stress
Symptom = Leaf curling
Main season (July to August)
Minor season (April to May)
Anthesis takes 2-3 months, up to 9
months
• Anthesis of a panicle takes 3-7 weeks,
up to 23 weeks
Rambutan Flowers
Female
Male
Induced Male
21-52 days
24-46 days
12-15 days
52 days
49 days
45 days
R134
42 days
38 days
35 days
40
31 days
60
28 days
157 days
147 days
80
24 days
21days
17 days
14 days
10 days
136 days
126 days
115 days
Silengkeng
7 days
3 days
0 days
105 days
94 days
84 days
73 days
63 days
52 days
42 days
31 days
21days
10 days
0 days
100
n=22
Naturally produced
hermaphroditic
male flowers
20
0
3
n=17
2.5
2
1.5
1
0.5
0
Flushing in Hawai’i
• Response to rainfall, heavy irrigation,
pruning, harvest
• Reduced by cool weather, heavy fruit
set and flowering even in presence of
rainfall
• Non-synchronous
• Takes 3-4 months to mature
• Flushes must be mature at time of floral
induction
• Main seasons (May-Jun.; Aug.-Sept.)
Fruiting in Hawai’i
• Seed filling 8-10 weeks after anthesis
• Aril/flesh development 10-12 weeks
after anthesis
• Harvest 16-20 weeks after anthesis
• BRIX readings >18%
• Main season (December-January)
• Minor season (August to September)
• Extended drought prolongs harvest 3-6
months longer
Binjai - Main Season (90 ft elevation)
BRIX
2.0
1.2
Length (in)
1.6
Diameter
1.0
Weight
0.8
1.2
0.6
0.8
0.4
0.4
0.2
0.0
0.0
2
4
6
8
10
12
14
16
18
Weight (oz)
Height
Weeks
After
Anthesis
14
16
18
BRIX
14.9
18.2
19.1
Weeks
After
Anthesis
16
18
20
BRIX
14.4
16.2
18.4
20
Weeks After Anthesis
Binjai - Minor Season (810 ft elevation)
2.0
1.6
Height
Diameter
1.2
Weight
1.0
0.8
0.5
0.4
0.0
0.0
2
4
6
8
10
12
14
Weeks After Anthesis
16
18
20
Weight (oz)
Length (in)
1.5