|
Chapter 25 Spinach
Link to Resource
Guide for Organic Insect and Disease Management
Recommended
Varieties
Listed in approximate order of maturity within each class.
| |
|
Pest Tolerance1
|
| Variety |
Leaf Type
|
DM2
|
WR3
|
CMV
|
| Spring Market |
|
|
|
|
Melody
|
semisavoy
|
1,2
|
-
|
H
|
Tyee
|
semisavoy
|
1,2,3
|
-
|
-
|
Coho
|
semisavoy
|
1,2,3
|
-
|
-
|
UniPack 151
|
semisavoy
|
1,2,3,4
|
-
|
H
|
| Fall Market |
|
|
|
|
Fall Green
|
semisavoy
|
1,2
|
M
|
H
|
Melody
|
semisavoy
|
1,2
|
-
|
H
|
Samish
|
semisavoy
|
1,2,3,4
|
M
|
-
|
Coho
|
semisavoy
|
1,2,3
|
-
|
-
|
UniPack 151
|
semisavoy
|
1,2,3,4
|
-
|
H
|
| Overwinter |
|
|
|
|
Vienna
|
savoy
|
1,2
|
-
|
H
|
Coho
|
semisavoy
|
1,2,3
|
-
|
-
|
Unipack 151
|
semisavoy
|
1,2,3,4
|
-
|
H
|
| Processing |
|
|
|
|
Melody
|
semisavoy
|
1,2
|
-
|
H
|
Tyee
|
semisavoy
|
1,2,3
|
-
|
-
|
Vancover
|
smooth
|
1,2,3
|
M
|
-
|
|
1: DM = downy mildew; WR = white
rust; CMV = cucumber mosaic virus
2: Resistant to downy mildew Race 1, Race
2, Race 3, and/or Race 4
3: L = low, M = moderate, and H = high level
of tolerance to pest. When disease tolerance for a particular variety
is unknown, line is left blank
|
Table of spinach disease resistant varieties
Planting
Methods
Spinach is a cool-season vegetable that
grows rapidly and develops the highest quality at temperatures of 55°
to 60°F and medium day lengths. The seed germinates between 32°
and 60°F, and young plants withstand temperatures as low as 15°
to 20°F. Seeding in the field can start as soon as the soil is tillable
in the spring and can continue through early May. Seeding for fall harvest
is done mainly in August. Seeding in cool regions of northern New York
for summer harvest is done in May and June. Spinach for an early spring
harvest is routinely overwintered on Long Island with seeding dates around
mid-September. Overwintering spinach in upstate New York is more of a
gamble but can be successful if the winter is mild. Seeding for overwinter
plantings in upstate New York should be done in early September.
|
| Table 25.1 Recommended
spacing. |
|
| Type |
Row1
(inch)
|
In-row
(plants/foot)
|
Seed depth2
(Inch)
|
| Fresh-market |
12-18
|
6-8
|
0.25-0.5
|
| Processing |
12
|
10-15
|
0.25-0.5
|
1:
For both fresh and processing markets, the most common arrangement
is 4 to 5 rows on 68-72 inch beds.
2: Plant seed deeper in warm, dry soil. Seeding to desired stand is
recommended rather than thinning. |
Crop rotation and disease management article
Fertility
Maintain a pH of 6.5 to 6.8 in upstate
New York and 6.0 to 6.2 on Long Island. Spinach is particularly sensitive
to soil acidity. See Table 25.2 for the recommended
rates of nitrogen, phosphorus, and potassium.
Cornell cover crop decision tool
See Cornell
article on nutrient deficiency symptoms
Go to Cornell Nutrient Analysis Lab website to find out how to get soil samples
tested.
Cornell Soil Health website and manual
SARE Publication: "Building Soils for Better Crops"
SARE publication: "Managing Cover Crops Profitably"
|
| Table
25.2 Recommended nutrients based on soil tests for spring grown spinach. |
|
|
N
pounds/acre
|
P2O5
pounds/acre
|
|
K2O
pounds/acre
|
Comments |
| |
Soil
Phosphorus Level
|
|
Soil
Potassium Level
|
|
| |
low
|
med.
|
high
|
|
low
|
med.
|
high
|
|
|
100-125
|
140
|
110
|
80
|
|
150
|
100
|
50
|
Total
recommended. |
|
50-75
|
140
|
110
|
80
|
|
150
|
100
|
50
|
Broadcast
and disk-in. |
|
30-50
|
0
|
0
|
0
|
|
0
|
0
|
0
|
Apply 3-4 weeks after seeding. |
|
| Table 25.3 Nonpathogenic
disorders. |
|
| Disorder |
Description |
| Air pollution |
On the upper
leaf surface this injury appears as stippling, flecking, mottling,
bleaching, and marginal leaf roll. Look for white, collapsed, irregular
patches. Ontario, Canada fact sheet on air pollution injury |
| Bolting |
Spinach bolts
in response to long days and high temperatures. Try slow-bolting varieties
or plant earlier. |
Harvesting
Most varieties reach harvest stage in
40 to 50 days under good growing conditions, but 50 to 70 days may be
required for early spring plantings. Spinach can be harvested when it
has only five or six leaves, but higher yields result when plants have
ten to 12 leaves.
Spinach is usually washed before marketing.
It is a very perishable product, but if picked early in the day, cooled
rapidly after harvest, and topped with ice it can be stored for ten to
14 days. Optimal storage conditions are 32°F and 95 to 100 percent
relative humidity.
See UC
Davis post harvest guide for spinach
See Cornell Report:
Food Safety Begins on the Farm
See Cornell
"Smart Marketing" series.
See USDA grade standards for bunched
spinach, leaf
spinach, and processed
spinach
See USDA
Marketing site
See current
wholesale prices from US markets
See "Fresh
Now from New York Farms"
SARE Publication: "Marketing Strategies for Farmers and Ranchers"
SARE Publication: "Direct Marketing Resource Guide"
Disease
Management
| Damping off | Seed
rot | Downy
mildew |
| White rust | Cucumber mosaic virus
|
SARE Publication: "A Whole-Farm Approach to Managing Pests"
Damping-off
and seed rot caused by Pythium spp.
|
UCONN
fact sheet on damping off
Time for concern: At seeding and in
postemergence stage
Key characteristics: Primarily a pre-emergence
damping off, but if soils are very moist, then post-emergence hypocotyl
rot can occur.
| Management
Option |
Recommendation
|
| Scouting/thresholds
|
No
thresholds have been established. |
| Note(s)
|
Rhizoctonia
may also cause damping-off of seedlings. There are no fungicides registered
on spinach that are specific for this organism. |
|
Resistant varieties |
No
resistant varieties are available. |
| Crop
rotation |
Rotation
may help to minimize buildup of fungi. Crop rotation and disease management article
Cornell cover crop decision tool
Cornell Forage Species Selection Tool |
| Seed selection/
treatment |
Use
seed treated with protective fungicide. See below. |
Site
selection,
Postharvest, and
Sanitation |
These
are currently not viable management options. |
|
Compound(s)
|
Comparing Environmental Risks of Pesticides
In the "Field Use EIQ" column is the range of EIQ (Environmental Impact Quotient) values for the rate range recommended for each pesticide (lower EIQ = lower environmental impact). Other pesticide risk models are useful for specific purposes. WIN-PST is required for some USDA NRCS conservation plans.
|
Common name
Trade
Name |
Rate/A
Product |
PHI
(days) |
REI
(hours) |
Field
Use EIQ |
Comments |
| mefenoxam
|
|
Ridomil
Gold EC or OLF
|
1-2
pt |
21
|
48
|
14-27
|
Specific for Pythium control. May be broadcast or banded over
the row, then incorporated in the top 2" of soil mechanically,
by rainfall, or by irrigation. |
|
Downy
mildew (Blue mold), Peronospora effusa
|
Penn
State spinach disease fact sheet
Time for concern: Season long, especially if over-wintered
inoculum is present.
Key characteristics: Appears as pale yellow,
irregular leaf spots on the upper surface, with corresponding grayish-purple
rot on the lower leaf surface.
|
Compound(s)
|
Comparing Environmental Risks of Pesticides
In the "Field Use EIQ" column is the range of EIQ (Environmental Impact Quotient) values for the rate range recommended for each pesticide (lower EIQ = lower environmental impact). Other pesticide risk models are useful for specific purposes. WIN-PST is required for some USDA NRCS conservation plans.
|
Common name
Trade
Name |
Rate/A
Product |
PHI
(days) |
REI
(hours) |
Field
Use EIQ |
Comments |
| azoxystrobin |
| Quadris
F |
12.3-15.4
fl oz
|
0
|
4
|
3-4
|
Do not apply more than 1 application of Quadris or Amistar (Group 11) before alternating with a fungicide that has a different mode of action. Make preventative applications on a 5-7 day schedule. Do not spray these products where spray drift may reach apple trees or use same sprayer to apply sprays to apple trees. |
|
|
4-5
oz
|
0
|
4
|
3-4
|
| copper compounds |
Kocide 3000 or OLF
Copper comparison article |
0.75-1.25lb |
0 |
24 |
13-22 |
|
| mefenoxam
|
|
|
1-2
pt
|
21
|
48
|
14-29
|
PPI.
May
be used 21 days after planting or after the first cutting at 0.25
pt/A. |
| phosphorous
acid |
|
|
2.5-5
pt
|
0
|
4
|
|
Do
not exceed 7 applications per season. |
| pyraclostrobin |
|
|
8-16
oz
|
0
|
12
|
|
No aerial application in NYS. Do not make more than 2 sequential applications before alternating to a labeled fungicide with a different mode of action (other than Group 11). |
|
White
rust, Albugo occidentalis
|
Penn
State spinach disease fact sheet
Time for concern: Season long, especially
if over-wintered inoculum source is present.
Key characteristics:Chlorotic areas appear on the upper leaf surface
with many shiny sori or blisters on the corresponding lower leaf surface.
|
Compound(s)
|
Comparing Environmental Risks of Pesticides
In the "Field Use EIQ" column is the range of EIQ (Environmental Impact Quotient) values for the rate range recommended for each pesticide (lower EIQ = lower environmental impact). Other pesticide risk models are useful for specific purposes. WIN-PST is required for some USDA NRCS conservation plans.
|
Common name
Trade
Name |
Rate/A
Product |
PHI
(days) |
REI
(hours) |
Field
Use EIQ |
Comments |
| azoxystrobin |
| Quadris
F |
6.2-15.4
fl oz
|
0
|
4
|
1-4
|
Do not apply more than 1 sequential application of Quadris or Amistar (Group 11) before alternating with a fungicide that has a different mode of action. Do not spray these products where spray drift may reach apple trees or use same sprayer to apply sprays to apple trees. |
|
|
2-5
oz
|
0
|
4
|
2-4
|
| copper
compounds |
Kocide 3000 or OLF
Copper comparison article |
0.75-1.25lb |
0 |
24 |
13-22 |
Label
varies with manufacturer and formulation. Phytotoxicity symptoms (small,
circular, brown spots) have been observed on spinach treated with
copper without an alkaline buffer. |
|
mefenoxam |
Ridomil
Gold EC
2 lb/gal |
1
- 2 pt
|
21
|
48
|
14-29
|
White
rust must be controlled in a preventative manner with the product
applied to the soil at planting and then again after cutting. |
| mefenoxam
+ copper |
Ridomil
Gold Copper
70W |
2.5
lb
|
21
|
48
|
54
|
Use
after Ridomil Gold EC or immediately after each repeated cutting. |
| pyraclostrobin |
|
|
8-12
oz
|
0
|
12
|
|
No aerial application in NYS. Do notmake more than 2 sequential applications before alternating to a labeled fungicide with a different mode of action (other than Group 11). |
|
Cucumber
mosaic virus (CMV) transmitted by aphids
|
Cornell
fact sheet on leafy greens and celery viruses
Penn
State spinach disease fact sheet
Time for concern: Early and main season
Key characteristics: Plants show severe mosaic
symptoms, stunting, and underdevelopment. When temperatures remain in
the mid-50’s or lower, veinal browning and necrosis can occur. See
Reference 1.
Insect
Management
| Green peach
aphid | Spinach
leafminer | Cabbage
looper |
| White rust | Cucumber mosaic virus
|
SARE Publication: "Manage Insects on Your Farm: A Guide to Ecological Strategies"
SARE Publication: "A Whole-Farm Approach to Managing Pests"
See pictures of GPA
life cycle
Time for concern: Spring and fall
Key characteristics: Adults vary in color.
They are about 1/16 inch long. Aphids are known to transmit viruses.
| Management
Option |
Recommendation
|
| Scouting/thresholds
|
Early
detection is important. Fields should be checked regularly. When scouting,
examine the entire plant. The following thresholds have been established
in the Midwest and may be applied here. For seedlings, apply an insecticide
when the average number of aphids per plant is greater than or equal
to one. For established plants, apply an insecticide if there are
four or more aphids per plant. If the average number of aphids per
plant is less than four, but any plants with more than 30 aphids,
the field should be rescouted in three days. See
Reference 2. |
| Natural enemies |
Naturally-occurring
predators, parasitoids, and pathogens help suppress infestations.
Use Reference
3
for identification of natural enemies. Coleomegilla
maculata lengi, Hippodamia
convergens, Coccinella
septempunctata, Cocinella tranversogutatta, Cycloneda munda, Hippodamia
variegata, Aphidoletes
aphiimyza, Aphidius matricariae, Diaeretiella rapae, Praon aguti,
Praon occidentale, Ephedrus incompletus, Lysephlebus testaceipes,
Aphelinus semiflavus,
Pandora neoaphidis.
Michigan State site "Enhancing Beneficial Insects with Native Plants"
ATTRA publication: "Farmscaping to enhance biological control" |
|
Note(s) |
Aphid
populations decline rapidly during periods of heavy rainfall. |
| Resistant varieties |
Plant
varieties with resistance to cucumber mosaic virus. See
25.1 Recommended Varieties. |
| Mulches
|
Reflective
foil mulches may slow down colonization of plants by winged aphids.
Direct seeding through the foil is recommended for maximum protection. |
| Insecticide
Resistance Management |
A classification
of insecticides based on their mode of action is available in pdf
format. This guide can be used to help avoid or delay the development
of insecticide resistance, as well as manage populations that have
developed resistance to a particular insecticide. It is a large
file - 97 page, 780k pdf file
Shelton,
A.M., W.T. Wilsey, and D. M. Soderlund. 2001. Classification of
insecticides and acaracides for resistance management
|
Crop
rotation,
Site selection,
Postharvest, and
Sanitation |
These
are not currently viable management options. |
|
Compound(s)
|
Comparing Environmental Risks of Pesticides
In the "Field Use EIQ" column is the range of EIQ (Environmental Impact Quotient) values for the rate range recommended for each pesticide (lower EIQ = lower environmental impact). Other pesticide risk models are useful for specific purposes. WIN-PST is required for some USDA NRCS conservation plans.
|
Common name
Trade
Name |
Rate/A
Product |
PHI
(days) |
REI
(hours) |
Field
Use EIQ |
Comments |
|
acetamiprid
|
|
|
2-4oz
|
7
|
12
|
1-2
|
|
|
diazinon |
|
|
0.5-1
pt
|
14
|
24
|
10-21
|
|
| imidacloprid
|
|
|
4.4-10.5 fl oz
fl oz
|
21
|
12
|
4-10
|
Do not apply as a foliar spray. |
|
|
3.75
fl oz
|
7
|
12
|
1
|
Do
not apply more than 18.75 fl oz per year as foliar spray. Allow 5
days between foliar applications. |
| pymetrozine
|
Fulfill
1.6F
0.5 lb/lb
|
2.75
oz
|
7
|
12
|
2
|
Apply
when aphids first appear but before populations build to damaging
levels. Do not exceed 5.5 oz/A per season. Allow 7 days between applications.
|
|
Ontario,
Canada leafminer fact sheet
Time for concern: Early in the season
Key characteristics: The spinach leafminer fly is 1/4 inch long
and gray with black bristles. Long, white eggs are laid on the undersides
of leaves. The larva is legless, yellowish white in color, and burrows
into the leaf. Damage appears as blisters on the surface of the leaves.
See Reference 2.
| Management
Option |
Recommendation
|
| Scouting/thresholds
|
Early
detection is important. Fields should be checked regularly. It is
necessary to apply an insecticide prior to the larvae mining into
the leaves. Look for leafminer eggs on the undersides of leaves and
any early sign of mining. In the Midwest, the threshold recommendations
suggest treatment if 50 percent of the plants have eggs or leafminers.
Thresholds for older plants depend upon the quality demanded by the
buyers, and most commercial growers would be concerned if more than
5 percent of harvested leaves had leafminer injury. See
Reference 2. |
| Natural enemies |
Naturally-occurring
predators, parasitoids, and pathogens help suppress infestations.
Use Reference
3
for identification
of natural enemies.
Michigan State site "Enhancing Beneficial Insects with Native Plants"
ATTRA publication: "Farmscaping to enhance biological control" |
| Preventive schedule |
A
preventive schedule is suggested. Begin applications when spinach
has two true leaves, and repeat every seven days. |
| Resistant varieties |
No
resistant varieties are available. |
| Sanitation
|
Remove
weed hosts, including lambsquarter, nightshade, chickweed, and plantain.
Deep-spring plowing will reduce overwintering leafminers. See
Reference 2. |
| Insecticide
Resistance Management |
A classification
of insecticides based on their mode of action is available in pdf
format. This guide can be used to help avoid or delay the development
of insecticide resistance, as well as manage populations that have
developed resistance to a particular insecticide. It is a large
file - 97 page, 780k pdf file
Shelton,
A.M., W.T. Wilsey, and D. M. Soderlund. 2001. Classification of
insecticides and acaracides for resistance management
|
Crop rotation,
Site selection, and
Postharvest |
These
are not currently viable management options. |
|
Compound(s)
|
Comparing Environmental Risks of Pesticides
In the "Field Use EIQ" column is the range of EIQ (Environmental Impact Quotient) values for the rate range recommended for each pesticide (lower EIQ = lower environmental impact). Other pesticide risk models are useful for specific purposes. WIN-PST is required for some USDA NRCS conservation plans.
|
Common name
Trade
Name |
Rate/A
Product |
PHI
(days) |
REI
(hours) |
Field
Use EIQ |
Comments |
| abamectin |
|
8.0-16.0 fl ozoz |
7 |
12 |
<1 |
Use an nonionic surfactant |
| cyromazine |
|
|
2.66 oz
|
7
|
12
|
|
Not
for use in Nassau/Suffolk Counties |
| diazinon |
|
0.5-1 pt |
14 |
24 |
10-21 |
|
| spinosad
|
|
|
1 |
4 |
2-3 |
Do not apply more than 29 fl oz per acre per season. |
|
|
|
1
|
4
|
2-3
|
Do not apply more than 9 fl oz per acre per season. |
|
See pictures of CL
life cycle
Time for concern: August 1 through
harvest
Key characteristics: White, rounded eggs the size of a pinhead
can be found on the undersides of leaves. Larvae are light green with
white strips along each side of the body. They may reach 1 1/2 inches
in length. See References 4 and 5.
| Management
Option |
Recommendation
|
| Scouting/thresholds
|
Record
the occurrence and severity of the cabbage looper infestation. No
thresholds have been established. |
| Natural
enemies |
Naturally-occurring
predators, parasitoids, and pathogens help suppress infestations.
Use Reference
3
for identification
of natural enemies. Hyposoter exigua, Litomastix, Geocoris
spp., nuclear
polyhedrosis virus, Podisus
maculiventris, Chrysoperla,
Trichogramma pretiosum, Trichogramma
ostriniae, Trichogramma exiguum, Bacillus
thuringiensis var. kurstaki, Granulosis
virus, Perillus bioculatus, Cotesia marginiventrus, Copidosoma
floridanum, Phryxe vulgaris, Voria ruralis, Wintemia quadripustulata,
Nomuraea
rileyi, Vairimorpha
necatrix
Michigan State site "Enhancing Beneficial Insects with Native Plants"
ATTRA publication: "Farmscaping to enhance biological control" |
| Note(s)
|
Adverse
weather conditions will reduce cabbage looper populations. |
| Resistant
varieties |
No
resistant varieties are available. |
| Insecticide
Resistance Management |
A classification
of insecticides based on their mode of action is available in pdf
format. This guide can be used to help avoid or delay the development
of insecticide resistance, as well as manage populations that have
developed resistance to a particular insecticide. It is a large
file - 97 page, 780k pdf file
Shelton,
A.M., W.T. Wilsey, and D. M. Soderlund. 2001. Classification of
insecticides and acaracides for resistance management
|
Crop
rotation,
Site selection,
Postharvest, and
Sanitation |
These
are not currently viable management options. |
|
Compound(s)
|
Comparing Environmental Risks of Pesticides
In the "Field Use EIQ" column is the range of EIQ (Environmental Impact Quotient) values for the rate range recommended for each pesticide (lower EIQ = lower environmental impact). Other pesticide risk models are useful for specific purposes. WIN-PST is required for some USDA NRCS conservation plans.
|
Common name
Trade Name |
Rate/A
Product |
PHI
(days) |
REI
(hours) |
Field
Use EIQ |
Comments |
|
Bacillus thuringiensis var. kurstaki |
|
|
0.25-0.5 lb
|
0
|
4
|
2-4
|
Most
effective underwarm weather conditions. |
|
|
0.12-1.5 lb
|
0
|
4
|
<1-10
|
| bifenthrin |
|
2.1 - 6.4 fl oz |
40 |
12 |
3-9 |
|
|
beta-cyfluthrin |
|
|
1.6-2.4 fl oz
|
0
|
12
|
5-8
|
|
|
methomyl |
|
|
1.5
- 3 pt
|
7
|
48
|
13-27
|
Do
not apply when the minimum daily temperature is 32°F or lower
or to seedlings less than 3" in diameter. Ground applications
only. |
| spinosad |
|
3-6 fl oz |
1 |
4 |
<1-2 |
Do not apply more than 29 fl oz t per acre per season. |
|
|
|
1
|
4
|
<1-2
|
Do not apply more than 9 fl oz t per acre per season. |
| zeta-cypermethrin |
*Mustang
MAX
0.8 lb/gal |
3.2-4
fl oz |
1 |
12 |
<1
|
Mustard spinach only |
|
Weed
Management
Key characteristics: Weed fact sheets provide a
good reference for common weed identification. See
Reference 6. Also see Virginia
Tech Weed Identification Guide.
Ontario,
Canada weed identification gallery
Cornell Weed Ecology and Management Laboratory website
Ontario, Canada weed identification |