Evaluation of Propagation Media 2008
Paul Fisher and Ernesto Fonseca, University of Florida, pfisher@ufl.edu, 352 226 4410.
Draft Internal Report. Not for publication or reproduction without permission of the authors.
May 8 2009
1
Executive Summary
The Young Plant Research Center periodically evaluates different propagation media available in the
market, and in this study chemical and physical qualities and greenhouse performance of several
types of loose and stabilized propagation media were tested.
This information is provided as a draft internal report for R&D and quality control by media
companies, improving media products, and not for promotion or publication. It is not to be
used to promote or criticize any product. Positive results are not an endorsement by the
University of Florida or the authors, and negative results similarly are not a criticism of the product.
Unrooted cuttings of three plant species (Sambucus nigra and Buddleia davidii provided by Spring
Meadow Nursery, MI and Osteospermum ecklonis provided by InnovaPlant, Costa Rica) were
propagated in each substrate over 40 days at the University of Florida research greenhouses. pH and
electrical conductivity (EC) of each substrate, a complete nutrient analysis by Quality Analytical
Laboratories, and rooting performance of cuttings, were measured in two evaluations on days 0 and
18 after sticking.
Acceptable rooting occurred in all stabilized and loose-filled media. Do not interpret these
results as identifying the best or worst growing medium – performance depends on the irrigation
practices and other specifics of the climate and management at the test site. Media companies are
being sent more detailed results on rooting in their individual media. For this report, we have
included photos of the rooting for comparison. For more detailed information, growers in the Young
Plant Research Center are welcome to contact me.
If we varied irrigation methods, our results would change. For example, we saw an excellent root
rating in Ellegaard pure coconut coir which had the highest water holding capacity – if we grew
plants “wetter” then a medium with low water holding capacity and more air porosity would be
favored.
Results also depend upon the batch and size of plugs tested (Jiffy and Blackmore Ellepots were
smaller than other stabilized media, and the components used in these media can be varied). The
measurement methods used also affect results. We chose to do photos and root ratings rather than
root dry weights because of the number of plugs tested and because separating roots is difficult in
stabilized media, but subjectivity results.
As a follow up to this report, we are considering developing a practical manual for growers on how
to test liner substrates, and will also do research on degradation of stabilized media in the
environment, rewetting, and pH drift. For the follow on research in 2009, we will be requesting new
samples from media companies.
2
1
Introduction
The Young Plant Research Center periodically evaluates different media available for cutting
propagation. Both loose and stabilized media were included in this study. We evaluated the rooting
of three plant species over a 40 day period, as well as chemical and physical qualities of the media.
Media performance is very dependent on the specific growing conditions. Therefore, our goal was
not to identify the “best” growing medium, but rather to run simple trials in order to gain experience
with the different media for future trials and discussions with media companies and growers.
2 Material and Methods
2.1
General Data
Species and cultivar
Buddleia davidii
‘Peakeep Peacock’,
Sambucus nigra ‘Eva
Black Lace’
Osteospermum
‘Lemon Symphony
Tray Count
Loose
Stabilized
Planting
Date
38
50
April 3
38
50
April 3
50
50
April 9
Root Evaluation
First
Second
April 21
May 6
(18 days)
( 32 days)
April 22
May 7
(19 days)
(33days)
May 2
May 13
(28 days)
(39 days)
Days under
Mist
12 days
12 days
14 days
Sambucus nigra ‘Eva Black Lace’ and Buddleia davidii ‘Peakeep Peacock’cuttings were received
from Spring Meadow Nursery, Michigan, and Osteospermum ecklonis ‘Lemon Symphony’ cuttings
were received from InnovaPlant, Costa Rica, in April 2008.
For loose-filled media, Sambucus and Buddleia were grown in 38-count, 5-in deep Star Nursery
trays (Gamma 10 Plastic Inc), and the osteospermum in 50-count Blackmore trays. We also planted
some trays of Sambucus and Buddleia in 50-count Blackmore trays and 32-count trays from Spring
Meadow with the Spring Meadow growing medium only. Spring Meadow media in the three tray
sizes are therefore labeled “Spring Meadow 32”, “Spring Meadow 38”, and “Spring Meadow 50”
Cuttings were grown under mist with clear water in a computer-controlled polycarbonate greenhouse
at the University of Florida for 12 to 14 days depending on cultivar and substrate, and were then
hand-irrigated with 150 ppm N from 17-4-17 neutral-reaction fertilizer (from Greencare Fertilizer)
with micronutrients at 1 ppm iron. Irrigation water alkalinity was 47 ppm.
3
Mist Frequency
Irrigation
Day
Night
Water
Fertilizer
8
9
Saturday, April 05
Sunday, April 06
Monday, April 07
Tuesday, April 08
Wednesday, April 09
Thursday, April 10
Friday, April 11
10
11
12
5-20min/ 6 Sec
35 min / 6 sec
90min/6sec
13
14
15
15-35min/ 6 seg
Off Mist
16
Off Mist
17-4-17 150 ppm
Temperature and light levels during the trial
Month
Average Temperature (F)
Daily Light Integral
(moles/m2/day)
71.5
13.7
April
76.8
14.9
May
A challenge in any media comparison trial is that optimum irrigation scheduling varies between
media and plants, and we did as best as possible to provide acceptable conditions by providing
benches with high and low mist settings and removing trays off mist as soon as they were adequately
rooted.
An additional limitation of this study was that although 50-count trays were requested from
manufacturers, in some cases the nearest size available was 72-count or similar.
4
Friday, April 18
7
Thursday, April 17
6
Wednesday, April 16
5
Tuesday, April 15
4
Monday, April 14
3
Sunday, April 13
2
Saturday, April 12
1
Friday, April 04
Day
Thursday, April 03
Mist Frequency
2.2 Substrates Included in the Study.
Stabilized Media
Components
Ellepot AP
Ellepot EP
Ellepot FC
Ellepot FP
Ellepot Knox
Ellepot Coco Press
Grow Tech HF
Grow Tech IP
Grow Tech MF
IHT Excel
IHT Q Plug
Jiffy
Oasis
Preforma
Loose Media
Ellegaard Coir
Fafard 1P
Fafard Rice
Pindstrup Coarse
Pindstrup Fine
Pindstrup Medium
Pro Mix with
Biofungicide
Pro Mix Mycorise
Pro Mix No
Biofungicide
Spring Meadow
Sun Gro LC1
Paper-wrapped pot. Paper consists of cellulose with an admixture of polyester for
reinforcement, and treated with fungicide. Greenway peat/perlite/vermiculite medium.
35 mm diameter.
Paper-wrapped pot. Paper consists of cellulose fibres with an admixture of polyester for
reinforcement. Greenway peat/perlite/vermiculite medium. 35 mm diameter.
Paper-wrapped pot. Paper consists of cellulose with a synthetic binder. Greenway
peat/perlite/vermiculite medium. 35 mm diameter.
Paper-wrapped pot. Paper consists of almost pure cellulose fibres with an admixture of
polyester for reinforcement. Greenway peat/perlite/vermiculite medium. 35 mm
diameter.
Ellepot AP paper. Verlite peat, perlite and vermiculite medium. 40 mm diameter.
Compressed coconut coir that quickly expands with water. 42 mm diameter.
Polymer / Peat hand-filled tray, 50-count
Polymer / Peat, 50-count
Polymer / Peat machine-filled tray, 50-count
Polymer / Peat, 72-count
Polymer / Peat, 72-count
Paper-wrapped pots with peat/perlite, peat/rice hulls, or coir, 72-count
Oasis foam, 10-count strips
Polymer / Peat, 50-count
Components
Coconut coir
80% Sphagnum peat moss, 20% horticultural perlite, wetting agent, starter nutrients
Same as 1P, but perlite substituted with rice hulls.
Peat, preplant, nutrient charge, wetting agent, limestone 0- 30 mm fibers
Peat, preplant, nutrient charge, wetting agent, limestone 0- 10 mm fibers
Peat, preplant, nutrient charge, wetting agent, limestone 5- 20 mm fibers
Peat / perlite. Enriched with SUBTILEX® (active ingredient: Bacillus subtilis MBI600
Sphagnum peat moss, endomycorrhize (Mycorise), started nutrients, lime stone, wetting
agents
Sphagnum peat moss, started nutrients, lime stone, wetting agents
Soil mix: Coarse, Pine bark, Peat moss, wetting agent
70% Sphagnum peat moss, 30% perlite, dolomitic limestone, gypsum, wetting agent.
2.3 Media-pH & EC Data
Complete nutrient analysis was conducted by Quality Analytical Laboratories (Panama City, FL) on
unused growing medium that had first been moistened to near container capacity for 7 days.
pH and EC were measured at the University of Florida on day 0 and day 18 (Sambucus and Buddleia
only) using the plug squeeze method. pH levels were averaged across the two species.
5
2.4
Root Evaluation
Roots were evaluated on 15 randomly-selected cuttings on two dates, and each cutting was classified
according to an eight-point scale. At the first root evaluation, all plants were in stages 0 to 4 in the
8-point scale. In the second root evaluation, roots were more established, and ranged from 2 to 8 on
the same scale. Osteospermum had an additional root evaluation classified to a seven-point scale.
Photos below show the evaluation scale.
2.5
Procedure for Analytical Testing of Media plugs
Definitions:
• A plug is the soil sample from the different companies that is wrapped in paper or held
together by a polymer.
• A cell is the plastic container into which you put the plugs.
1. To begin measure the plug height from the bottom plane to the top plane using a ruler with cm
markings.
2. Measure the cell volume (for loose-filled media) by placing tape over the bottom drain hole.
Measure the cell. Then fill the cell completely with distilled water (dH2O). Measure the mass of the
cell filled with water. Subtract these measurements and the difference is the volume of the cell. (1 g
dH2O = 1 mL d H2O)
3. To take the media (plug) volume (for stabilized media) first coat the plug with parafilm wax.
Fill a beaker to the rim with distilled water (dH2O). Zero the scale with the catch container on it.
Place filled beaker in catch container and submerge the wax covered plug causing the water to
overflow. Mass catch container with overflow. Because scale was zeroed with catch container this
is the mass of the water only. This gives volume of plug in mL (1 g dH2O = 1 mL d H2O).
4. To measure the air volume, first cover the drain hole of the cell with tape to prevent water from
leaking. Next with the plug inside the cell add distilled water (dH2O) until the water level reaches
the top of the plug with no excess water on top of the plug. Mass the cell and plug. After this
remove the tape from the bottom of the cell to allow excess water to drain. After cell is done
draining mass cell and plug. The difference in mass (g) is the volume (mL) of air in the cell and
plug that was occupied by water (1 g dH2O = 1 mL d H2O).
5. The air porosity is a calculated value. It is the percentage of the cell volume that is occupied by
air when the plug is in it and is at maximum water holding capacity. To calculate air porosity, use
the following formula:
Air porosity = air volume
Cell volume
6. To calculate the water holding capacity take the fresh weight of the plugs (g). Place plugs in a
drying oven for 24 hours at 110oC. Then take the dry weights of the plugs. The difference in mass
is equal to the amount of water (mL) that was present in the plugs(1 g dH2O = 1 mL d H2O).
6
7. The water porosity is a calculated value. It is the percentage of the cell volume that is occupied
by water when the plug is in it and is at maximum water holding capacity. To calculate water
porosity, use the following formula:
Water porosity = water volume
Cell volume
8. The total porosity (mL) is the addition of the water and air volume.
9. The total porosity (%) is the total porosity (mL) divided by the cell volume.
10. The media (mL) is a calculation of the media volume based on the air and water volume in the
cell. To get this value subtract the total porosity (mL) from the cell volume.
11. The media % is a calculated value. It is the percentage of the cell volume that is occupied by
media when the plug is in it and is at maximum water holding capacity. To calculate media %, use
the following formula:
Media % = cell volume – media (mL)
7
2.6
2.6.1
Root Evaluation Scale
Stabilized Media Root Rating
Sambucus, Buddleia and Osteospermum
First Evaluation
2.6.2 Loose Media Root Rating
Sambucus, Buddleia
First Evaluation
Osteospermum
First Evaluation
Second Evaluation
Second Evaluation
Second evaluation
8
3 Results
3.1 Physical quality data
Based on average of three samples for each media.
Stabilized media
Media
EllePot AP
Ellepot Coco
Ellepot EP
Ellepot FC
Ellepot FP
Ellepot Knox
Grow Tech IP
Grow Tech HF
Grow Tech MF
IHT Excel
IHT Q Plug
Jiffy Carefree
Jiffy Coir
Jiffy Rice Hulls
Preforma
Oasis
Tray
volume
(mL/cell)
67.0
67.0
67.0
67.0
67.0
67.2
67.0
67.0
67.0
67.0
67.0
67.0
67.0
67.0
67.3
51.0
media
height
(cm)
3.7
3.0
3.7
3.5
3.5
3.3
4.3
4.4
4.4
3.7
6.2
4.3
3.1
4.4
4.6
5.0
Plug
volume
(mL)
27.4
27.4
22.2
18.2
22.3
37.2
45.0
36.4
49.7
30.2
65.5
24.0
16.3
21.6
48.8
39.0
air
volume
(mL)
19.7
15.7
22.5
21.0
22.1
15.9
8.2
19.7
5.0
3.7
5.6
26.7
27.7
29.1
11.6
6.8
air
porosity
%
29%
28%
26%
23%
26%
26%
30%
34%
33%
32%
31%
33%
33%
33%
19%
13%
water
water
media
total air + total
holding
media
porosity volume
water porosity
capacity
(%)
(%)
(mL)
(mL)
(%)
(mL)
19.1
29%
28.2
42%
38.8
58%
29.8
44%
21.5
32%
45.5
68%
26.2
39%
18.3
27%
48.7
73%
24.4
36%
21.7
32%
45.3
68%
25.5
38%
19.4
29%
47.6
71%
28.8
43%
28.5
42%
39.0
58%
34.5
51%
24.8
37%
42.7
63%
21.6
32%
26.2
39%
41.3
61%
29.5
44%
33.0
49%
34.5
51%
25.3
59%
14.0
33%
29.0
67%
32.9
48%
30.6
44%
38.4
56%
23.3
35%
17.0
25%
50.0
75%
20.9
31%
18.4
27%
48.6
73%
23.6
35%
14.4
21%
52.6
79%
27.4
41%
24.8
37%
42.4
63%
39.9
78%
4.2
8%
46.8
92%
Loose media
Tray
volume
(mL/cell)
Media
Ellegard Coir
Fafard 1P
Fafard Rice
Pindstrup Coarse
Pindstrup Fine
Pindstrup Medium
Pro Mix Mycorise
Pro Mix Biofungicide
Spring Meadow
SunGro LC1
67.0
67.0
67.0
67.0
67.0
67.0
67.0
67.0
67.0
67.0
media
height
(cm)
n.a
n.a
n.a
n.a
n.a
n.a
n.a
n.a
n.a
n.a
Plug
volume
(mL)
67.0
67.0
67.0
67.0
67.0
67.0
67.0
67.0
67.0
67.0
air
volume
(mL)
15.5
25.8
18.3
27.2
24.9
22.3
20.9
23.8
25.4
23.1
air
porosity
%
23%
39%
27%
41%
37%
33%
31%
35%
38%
34%
water
water
media
holding
porosity volume
capacity
(%)
(mL)
(mL)
42.8
30.2
31.6
35.2
34.9
37.0
32.5
30.8
26.0
30.9
64%
45%
47%
53%
52%
55%
49%
46%
39%
46%
8.7
11.0
17.0
4.6
7.2
7.7
13.6
12.4
15.6
13.0
media
(%)
13%
16%
25%
7%
11%
11%
20%
19%
23%
19%
total air + total
water porosity
(mL)
(%)
58.3
56.0
50.0
62.4
59.8
59.3
53.4
54.6
51.4
54.0
87%
84%
75%
93%
89%
89%
80%
81%
77%
81%
9
3.2 Nutrition, pH and EC analyses (Quality Analytical Laboratories)
Unused media, saturated medium extract, after 7 days near container capacity
Stabilized Media
Ellepot AP
Ellepot Coco
Ellepot EP
Ellepot FC
Ellepot FP
Ellepot Knox
Grow Tech HF
Grow Tech IP
Grow Tech MF
IHT Excel
IHT Q Plug
Jiffy Carefree
Jiffy Coir
Jiffy Rice Hulls
Oasis
Preforma
Loose Media
Ellegard Coir
Fafard 1P
Fafard Rice
Pindstrup Coarse
Pindstrup Fine
Pindstrup Medium
ProMix Biofungicide
ProMix Mycorise
ProMix No Biofungicide
Spring Meadow
SunGro LC1
NO3-N NH4-N
(ppm) (ppm)
ND
ND
45.7
24.7
1.7
ND
1.5
0.4
2.0
0.1
40.9
16.8
3.9
2.2
5.1
ND
0.1
ND
1.6
5.1
33.4
19.3
58.0
19.6
46.4
1.4
3.8
5.8
12.8
ND
0.5
0.2
P
K
Ca
Mg
SO4-S Fe
Mn
B
Cu
Zn
Mo
Na
Al
Si
Cl
(ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm)
7.7
63.7
78.8
33.5 133.7
0.0
0.1
0.1
0.0
0.0
0.0
21.1
0.2
3.2
7.8
42.2 193.6
11.1
3.6
2.7
0.0
ND
0.2
0.0
0.0
0.0
49.0
0.2
4.7 190.0
5.9
47.6
45.1
23.3
93.3
0.0
0.1
0.1
0.0
0.0
0.0
15.3
0.2
2.4
4.7
7.3
54.0
57.9
28.2 112.2
0.0
0.1
0.1
0.0
0.0
0.0
17.8
0.2
2.5
6.7
5.3
41.4
39.9
19.2
79.6
0.1
0.0
0.1
0.0
0.0
0.0
13.7
0.2
2.8
4.9
16.9
94.1
68.2
52.1 120.3
1.1
0.3
0.1
0.0
0.2
0.0
13.2
0.4
8.5
17.0
22.5
16.8
16.6
13.2
9.7
0.2
0.0
0.1
0.0
0.2
0.0
13.9
0.2
2.2
37.0
21.3
63.9
58.2
51.7 127.3
0.1
0.0
0.1
0.0
0.4
0.0
27.9
0.2 10.5
26.0
6.2
21.3
42.9
33.6
26.3
0.1
0.0
0.1
0.0
0.4
0.0
22.9
0.3
8.8
56.0
31.0
34.5
33.1
20.8 144.0
0.5
0.0
0.9
0.0
0.5
0.0 232.9
0.5
5.4 140.0
49.5
36.1
31.6
16.4
21.5
2.2
0.6
0.3
0.1
0.1
0.0
39.3
0.3
2.3
19.0
52.9
20.3
80.4
77.9 107.0
0.1
0.0
0.2
0.0
0.0
0.0
28.2
0.3
9.1
15.0
15.9
91.1
34.8
5.8
5.6
0.1
0.1
0.2
0.0
0.2
0.0
21.3
0.3
1.6
39.0
49.7
12.7
37.5
30.1
42.7
0.0
0.0
0.1
0.0
0.0
0.1
13.1
0.2 21.9
11.0
5.8
3.9
46.7
24.0
77.0
0.1
0.1
0.1
0.0
0.1
0.0
0.2
0.2
0.7
0.9
0.3
3.3
0.2
0.3
0.3
0.0
ND
0.1
0.0
0.0
0.0
1.0
0.2
0.3
2.6
NO3-N NH4-N
(ppm) (ppm)
68.0
38.4
34.7
15.1
62.4
24.6
1.6
ND
15.7
ND
41.5
10.2
74.8
9.5
99.8
14.3
0.6
0.3
119.2
50.8
66.7
31.4
P
K
Ca
Mg
SO4-S Fe
Mn
B
Cu
Zn
Mo
Na
Al
Si
Cl
(ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm)
34.8 208.6
17.5
5.3
6.4
0.1
0.1
0.3
0.0
0.0
0.0
50.4
0.2
2.4 170.0
11.6
52.2
42.1
37.8
58.1
0.6
0.3
0.1
0.0
0.2
0.0
14.9
0.5
5.3
8.5
28.6 131.2 113.1
37.4
81.3
1.4
0.8
0.1
0.0
0.1
0.0
19.0
0.6 11.3
18.0
25.7
67.7
41.8
7.2
23.3
1.2
0.2
0.1
0.0
0.1
0.2
10.6
1.7 10.6
5.7
14.4
56.4
74.7
9.0
25.9
0.7
0.2
0.1
0.0
0.1
0.0
12.8
1.1
8.4
6.9
30.1
79.2
71.2
13.0
33.9
1.7
0.4
0.1
0.0
0.1
0.0
12.4
2.7 14.9
7.7
18.5
52.7
93.3
25.5
37.1
0.7
0.4
0.2
0.0
0.9
0.0
43.9
0.3
5.5
45.0
15.2
76.0 110.8
26.9
45.1
1.4
0.6
0.3
0.1
0.7
0.0
27.8
0.5
4.8
14.0
12.1
46.4
43.3
11.0
32.3
0.3
0.3
0.1
0.0
1.5
0.0
23.6
0.3 32.3
12.0
10.3 124.5
56.8
69.7
91.2
2.0
0.9
0.2
0.1
0.9
0.0
23.9
4.5 10.3
17.0
24.2 100.7 112.5
38.6
82.7
0.7
0.8
0.2
0.0
0.1
0.0
22.3
0.8 82.7
5.1
10
3.3 pH and EC Test at UF (Plug Squeeze)
pH and EC summary table for loose and stabilized Media. The second pH and EC test shows the
average of Buddleia and Sambucus, 18 days after planting. Plants were mist-irrigated for 12-14 days
with clear water, followed by hand-irrigation with 150 ppm N from 17-4-17 neutral-reaction
fertilizer (from Greencare Fertilizer) with micronutrients at 1 ppm iron. Irrigation water alkalinity
was 47 ppm.
Initial pH and EC (Day 0)
Stabilized
Media
Ellepot AP
Ellepot Coco
Ellepot EP
Ellepot FC
Ellepot FP
Ellepot Knox
Grow Tech HF
Grow Tech IP
Grow Tech MF
IHT Excel
IHT Q Plug
Jiffy Carefree
Jiffy Coir
Jiffy Rice Hull
Oasis
Preforma
Loose
Media
Ellegaard Coir
Fafard 1P
Fafard Rice Hulls
Pindstrup Coarse
Pindstrup Fine
Pindstrup Medium
ProMix Mycorise
ProMix No Biofungicide
ProMix Biofungicide
Spring Meadow
Sun Gro LC1
EC
pH
5.9
6.2
5.8
6.0
6.0
5.5
6.0
6.7
6.5
5.5
5.1
5.7
5.1
5.9
5.9
6.1
pH
0.63
0.92
0.67
0.64
0.66
4.67
0.20
0.52
0.27
0.83
0.78
1.63
1.39
1.18
0.77
0.68
EC
6.1
6.1
5.8
5.9
6.2
5.1
6.0
6.1
6.3
6.2
4.1
1.5
1.45
1.36
1.21
1.36
1.32
1.71
1.54
1.19
3.80
3.60
pH and EC (Day 18)
Stabilized
Media
Ellepot AP
Ellepot Coco
Ellepot EP
Ellepot FC
Ellepot FP
Ellepot Knox
Grow Tech HF
Grow Tech IP
Grow Tech MF
IHT Excel
IHT Q Plug
Jiffy Carefree
Jiffy Coir
Jiffy Rice Hull
Oasis
Preforma
Average
pH
EC
6.20
0.82
6.55
0.78
6.30
0.99
6.25
0.76
6.20
0.86
5.80
0.91
6.65
0.83
6.50
1.16
6.80
0.94
5.75
0.92
5.55
0.66
6.10
0.89
5.60
0.83
6.35
0.98
6.10
0.86
6.10
0.94
Loose
Media
Ellegard Coir
Fafard 1P
Fafard Rice Hulls
Pindstrup Coarse
Pindstrup Fine
Pindstrup Medium
ProMix Biofungicide
ProMix Mycorise
ProMix No Biofungicide
Spring Meadow
SunGro LC1
Average
pH
EC
6.25
0.84
6.50
0.64
5.80
0.88
5.60
0.99
6.30
0.83
5.05
0.63
6.45
0.92
6.30
0.86
6.60
0.74
6.40
0.94
4.40
0.60
11
3.4
Photos Comparing Rooting in All Media
Species
Stabilized Media
Before sticking
12
Sambucus 1st evaluation April 22 (after 19 days)
13
Sambucus 2nd evaluation May 7 (after 33 days)
14
Sambucus Loose Media May 15 (after 42 days)
15
Buddleia 1st Evaluation April 18 (after 18 days)
16
Buddleia 2nd evaluation May 6 (after 32 days)
17
Osteospermum 1st evaluation May 2 (after 28 days):
18
Osteospermum 2nd evaluation May 13 (after 39 days)
19