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GREEN PEANUT PRODUCTION
Varieties: Green
peanut production starts with variety selection because the objective is to grow
the highest yielding variety that you can successfully market. Green peanut
markets can be locally specialized. That is, consumer acceptance and
marketability is influenced by factors such as pod size, shape, kernel skin
color, multi-kernel pods, and flavor. Despite this influence of tradition, a
bright-hulled peanut with good flavor usually sells well and develops a market.
Valencia types - Some consumers prefer the distinctive
flavor, multi-kernel pod characteristics, and red seed coat of Valencia
peanuts. In general Valencia peanuts have lower yield than Virginia types and
their smaller pod size is also a disadvantage in hand picking.
Georgia Red - Tends to yield higher and have darker red seed coat
than other Valencia types.
Valencia A and Valencia C - These two varieties are very similar in
yield and pod characteristics.
Virginia types - Virginia type peanuts are desirable in the green
market because of their high yield, large pod size and good flavor.
Gregory - This variety’s large pods and bright hull make it an
excellent choice for green peanut production. Gregory also has moderate
tomato spotted wilt resistance. Gregory has a high calcium requirement.
NC 7 - This is a large-kerneled, bright-hulled peanut with
excellent flavor. It has been a standard in the green market despite not
having the highest yield.
NC V11 - High yield and some virus resistance, but a smaller pod than
Gregory or NC 7.
Va 92R - This variety is a high-yielding Virginia type under S. C.
conditions. It typically outyields NC 7 by about 10%. However, Va 92R kernel
size is smaller than NC 7 and the hull is darker.
Runner types - Runner type peanuts get their name from the fact that
they tend to have a prostrate or running growth habit. These are the
"peanut butter peanuts" and although they have excellent flavor,
most varieties are too small for efficient hand-picking.
C99R - This variety has a relatively large pod for a runner type and
has the advantage of high yield and good tomato spotted wilt resistance. Its
disadvantage is slower maturity.
Land Rotation: It is very important to maintain a minimum 3-year
rotation (2 years out of peanuts or any other legume, 3 years better).
Rotation is the basis for controlling pod disease; controlling pod disease is
the key to a bright hull; and a bright hull is the key to marketability.
Planting Date: Green peanuts are planted for the market window rather
than for optimal production conditions. The ideal time to plant peanuts in S. C.
is the first week of May. This timing minimizes damage from tomato spotted wilt
virus and gives the shortest production interval (about 100 days after
planting). But since some peanuts have to be planted much earlier (late-March to
April) to hit the best market price window, they will have more tomato spotted
wilt virus damage and a longer development period. See virus management below.
Seeding Rate: Plant 5 seed per row foot. A good stand and rapid ground
cover helps control tomato spotted wilt virus.
Row Spacing: Conventional row spacing is 38", narrower row spacing
and/or twin-row production help to reduce tomato spotted wilt virus by covering
the ground more quickly.
Land Preparation: Traditional bottom plowing suppresses weed germination
and turns down potash to reduce competition for Ca uptake in the pegging zone. But
we can make top peanut yields without bottom plowing. Subsoil & bed works so
you can plant peanuts just like cotton. You can also plant flat. We can control
diseases without bottom plowing. Strip-till has given equivalent yields on
lighter soils and we have been able to control weeds without preplant
incorporated (PPI) herbicides under irrigated strip-tillage conditions.
Strip-tillage into a killed cover crop reduces tomato spotted wilt virus, but
also results in more residue in the inverted vines after digging.
Fertility: Use Rhizobium inoculant on new peanut land. Liquid
in-furrow inoculant or seed treatments are recommended since in-furrow granular
inoculants usually stop-up in the delivery tube. Nitrogen application (30 - 50
lb/ac) is recommended on new ground if the inoculant fails.
pH 5.8 - 6.2 target
P and K are applied by soil test. Peanuts respond best to residual
fertilizer. Adequate residual potash is especially important if you don’t
bottom plow. Excess K in the pegging zone interferes with Ca uptake causing
pod rot, so avoid potash application in the spring if you can’t turn it
under.
Calcium - High soil Ca is critical to quality peanut production,
especially for Virginia types. Apply 300 lb/ac of Ca (1500 lb landplaster) at
first bloom to reduce pod rot and brighten hulls. Half this amount can be used
if it is applied in a band over the pegging zone. Fall liming is also
beneficial in maintaining at least 600 lb Ca/ac and a 3:1 Ca to K ratio in the
pegging zone.
Boron - Apply 0.5 lb B/ac (2½ lb/ac Solubor) at early bloom or
split into two 0.25 lb/ac applications. Boron can be tank-mixed with
fungicide.
Zinc toxicity - Peanuts are very sensitive to zinc. Stunted plants
with split stems are a sign of zinc toxicity. Check zinc levels on any new
land prior to planting, especially in old peach orchard fields or where zinc
has been used for high yield corn production. Zinc toxicity also occurs on old
building sites or around stock pens which had galvanized roofs. Soil test zinc
levels as low as 5 lb/ac can cause toxicity when the soil pH is below 6.0.
Liming to increase soil pH can reduce zinc toxicity in contaminated soils.
Irrigation: Green peanuts’ greatest need for water is from pegging
until a week before digging. A rule of thumb is to supply 1.5 inches per week
minus whatever rainfall you get. Irrigation is critical in peanut production
because it allows you to take advantage of other inputs. Irrigation is used to
water in herbicides (e.g. Prowl, Sonalan, Dual, Cadre); fungicides (Abound,
Folicur); and insecticide (Lorsban). Without timely rain or irrigation these
inputs are much less effective.
Weed Control: Timing is everything in weed control. Good weed control is
a must to reduce harvest losses. There are a lot of possible variations in a
weed control program for the many combinations of problem weeds, but an example
program would be: Prowl or Sonalan PPI; Dual PRE (watered in); Gramoxone +
Basagran to kill the first flush of small weeds; or Cadre (note 90 day preharvest interval); possibly followed
by 2,4-DB (Butyrac) for escape broadleaves or Select for escape grasses. See the weed response chart.
Note: Excessive rates of DNA herbicides (Prowl, Sonalan) in the pegging
zone cause severe peg injury and yield reduction.
Disease Control:
Tomato spotted wilt virus (TSWV). This virus is transmitted to peanuts
by thrips. TSWV reduces yield and causes shriveled, misshapen pods. The
disease is more of a problem on green peanuts due to the use of early planting
dates followed by a sequence of later plantings.
TSWV Control: "It’s all over when the planter leaves the
field":
1. Varietal Resistant - The only partially resistant varieties which are
suitable for the green market are Gregory, NC V11, and C99R.
2. Planting Date "window" - Planting the first two weeks of May
reduces TSWV, but this is not practical for green production. Staggered
planting dates in the same field increase virus problems on later plantings.
3. Seeding Rate - 5/row ft.
4. Thimet In-furrow - Thimet 20 G (5 lb/ac) reduces TSWV injury
5. Strip-tillage - reduces TSWV in SC
6. Twin-row - faster ground cover means less virus.
Fungicide Program for White mold, Limbrot, and Leafspot:
The fungicide program used for green peanuts is significantly different than
what is recommended for dry peanut production because a green peanut production
period is much shorter (about 100 days vs. 140 days) and the crop value is
higher. The key to producing a bright-hulled cosmetically pleasing product is to
prevent white mold and Rhizoctonia limbrot from getting started. Alternating
different fungicide chemistries reduces the potential for developing resistant
strains of soil and foliar diseases. Alternating fungicides also gives some
insurance against the failure of one product alone. For example, Abound is a
better preventative, but Folicur is a better curative product against white
mold. Abound is a better limbrot material but Folicur is better against leafspot.
It makes sense to use them both. The following schedule is only a guideline. It
needs to be modified to account for opportunities to wash Folicur and Abound
into the soil if no irrigation is available. The preharvest interval is 14 days
for both Abound and Folicur.
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1st spray
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45 DAP
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Abound 18 oz
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OR |
Folicur 7.2 oz
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2nd spray
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60 DAP
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Folicur 7.2 oz
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Abound 18 oz
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3rd spray
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75 DAP
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Abound 18 oz
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Folicur 7.2 oz
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Note: DO NOT use any adjuvants, stickers, or crop oil with Folicur or
Abound. The goal is to wash fungicide into soil. Spray Folicur and Abound before
irrigation or rain when possible. Wait 24 to 48 hours to irrigate in order
to also get leafspot control from Abound or Folicur application.
CBR - Cylindrocladium black rot is caused by a soil fungus which
occurs in the same fields from year to year, often in low spots. Rotation and
fumigation (Vapam 10 gal/ac) can be used to control CBR. There is also
increasing evidence that Folicur and Abound provide some suppression of CBR.
Among the Va. types; NC 12C and Perry have some resistance to CBR.
Insect Control:
Thrips - use in-furrow Thimet 20G 5 lb/ac or Temik 15G 4 - 6 lb/ac.
Soil Insects - Apply Lorsban (13 lb/ac) at early pegging (about 45 DAP)
to reduce pod damage by lesser cornstalk borer and wireworm. In addition to
reducing pod damage, Lorsban helps brighten hull color by improving white mold
control. Unfortunately Lorsban also causes outbreaks of corn earworm,
granulate cutworm and spider mites later in the season. However, irrigation
and the shorter growing season used in green peanut production lessens the
possibility that these pests will require control.
Foliage caterpillars - Look for worms particularly during the last week
of July and first week of August. Granulate cutworm is also a problem late in
August where Lorsban is used. The treatment threshold is 4 worms per row ft.
Rank-growing peanuts can tolerate 8 foliage feeding worms per row ft. Keep
corn earworm off of stressed peanuts especially. Asana, Karate, Danitol, and
Lannate are labeled on peanut.
Spider mites - Irrigation is the best spider mite defense. Comite and
Danitol are labeled for mite control. Mites are less of a problem if Lorsban
is not used.
Harvest maturity: Green peanuts typically mature in 90 to 110 days,
depending on planting date. Valencia types require a shorter season than
Virginia types. Pods which aren’t filled by the kernel are too young and
pods with dark internal hull color are too mature. Dig when most pods are
within this range.
Summary: The key to high quality, 120 bu/ac green peanuts is timely
management decisions (and water of course). Poorly timed crop investments are
often wasted ones.
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