Does EQIP pay for row cover, hoops, clips, or sandbags?

The High Tunnel System Initiative FAQ says financial assistance is provided only for the structure itself; the grower is responsible for electricity, venting, lighting, and similar additions. Frost cloth, inner hoops, snap clamps, pegs, and sandbags sit with those grower costs. Pennsylvania’s seasonal high-tunnel page says producers can install heating, ventilation, or electrical systems at their own expense — same structure-only split. CPS 325 says the practice does not include greenhouses or low tunnel systems. Inner cloth on hoops inside a funded house is still not a row-cover payment. This page does not invent a dollar. Confirm with your county NRCS office. See what EQIP will not pay for.

What weight row cover inside a high tunnel — 0.5, 0.9, or 1.5 oz?

Only the figures the pages printed. UAEX MP586: 0.5–2.0 oz/sq. yd; thicker covers offer more frost protection; a thicker frost cloth can cut light 50 percent or more. Purdue HO-297 used a 0.55 oz./sq.yd. cover for its all-day DLI table (72% of outside DLI without cover vs 48% with it). Purdue HO-330 assumes at least medium-weight cover below 25°F and a double layer below 10°F. Purdue Hotline compared 1.5 oz/sq.yd Agribon AG-50 on a wire hoop. Johnny's 2021 vendor chart (not a field trial): AG-19 0.55 oz / 2–4° / 85% light; AG-30 0.9 oz / 4–6° / 70%; AG-50 1.5 oz / 6–8° / 50%; AG-70 2.0 oz / 8+° / 30%. AG-15 is named as no frost protection — that is insect barrier, not this page. Those numbers stay labeled. Amazon packs on this page are sizes only.

Do I float row cover on hoops or lay it on the crop?

Both appear on fetched pages. UAEX: often suspended on hoops, but they can also rest on the plants; cloth frozen to leaves can tear plants when you pull it. UKY: place covers over hoops so tender leaves do not freeze to the fabric. Cornell: medium-weight cover supported on hoops, 5–10 F, more on colder nights. Purdue HO-297: sometimes on the crop, sometimes on wire or conduit hoops; moisture condensing on the fabric increases insulation. Penn State: floating row covers or low tunnels trap heat in the canopy. Johnny's 2015 insert: float on the crop or over #9 wire / hoop loops / Quick Hoops; anchor with snap clamps, hand pegs, sand bags, or a soil furrow. Inner hoops inside a walk-in house are not a field low tunnel and not a CPS 325 practice.

When do I pull row cover on a sunny day?

Cornell: covers must be removed during the day for light transmission. Purdue HO-297: even a lightweight cover left on all day cut DLI by about one-third; remove it during the day to increase light; in late fall/winter pull it once the tunnel is above freezing; leaving it on cuts light, soil-heat storage, and raises humidity; a clear cover left on a sunny day can get too hot; vent so the house stays below 80°F — air can go from below freezing to over 80°F in a few hours. Purdue HO-330 vents so as not to allow above 80°F. UKY: do not leave covers on for prolonged periods in winter. Johnny's 2015 insert: remove if temperature exceeds 90°F/32°F under the cover — that paired figure is Johnny's printed line, not a Tunnel Spec conversion. Purdue Hotline: a 1.5 oz cover on hoops added about 12°F when the house was near 0°F and almost nothing near 50°F. Those are the printed sentences.

Does inner row cover cause condensation and disease?

Rutgers FS1267: inner row cover adds insulation but reduces airflow and increases foliar-disease chance, and it reduces light; keep lettuce leaves as dry as possible (gray mold, lettuce drop). Cornell greens: powdery mildew on lettuce is a big problem under low light and high humidity in late fall and early winter. Cornell winter-greens disease page: do not put row cover over wet plants; some high-tunnel downy mildew on spinach was associated with covering wet leaves; vent as often as temperature permits. Purdue HO-297: condensate on the fabric increases insulation — and leaving cover on all day maintains higher humidity near the plants. This page is not a spray schedule. Pest cards stay on high-tunnel pest control.

How is this different from a caterpillar / low tunnel or insect netting?

A field low tunnel or caterpillar is a stand-alone short house. CPS 325 says the practice does not include greenhouses or low tunnel systems; a funded high tunnel still has to be a manufactured kit at least 6 feet at the peak. Inner frost cloth on low hoops inside that kit is a secondary cover — UAEX, Penn State, Johnny's, and Purdue describe it that way. The caterpillar / alternatives pages own the outdoor low-tunnel SKU race. Insect netting is a different fabric. Johnny's 2021 chart: Agribon+ AG-15 does not provide frost protection; ProtekNet is exclusion mesh. SWD 80-gram sidewall ratings stay on high-tunnel insect netting. Do not treat frost cloth as exclusion mesh or a low-tunnel kit.

Inner frost cloth · double cover · not a kit

How to use row cover inside a high tunnel: frost cloth weights, low hoops, and when to pull it (sourced)

Growers search high tunnel row cover, frost cloth inside a hoop house, and double cover winter greens when the film is already on and nights still drop. This page is the inner-cloth sibling — floating frost blanket on low hoops inside a walk-in house, 0.5 / 0.9 / 1.5 oz/sq yd weights, clips, when to pull it on a sunny day, and the condensation / disease caveat. Crop scheduling stays on high-tunnel winter lettuce. Heaters and soil as night heat stay on how to heat a high tunnel. A field caterpillar or low tunnel is a different structure and stays on high tunnel alternatives and caterpillar vs high tunnel. Exclusion mesh stays on high-tunnel insect netting. It is not a commercially manufactured high-tunnel kit and not a USDA payment schedule.

Quotes copied 23 October 2026, about 03:20 UTC from live UAEX MP586, Purdue HO-330 / HO-297 and Vegetable Crops Hotline, Rutgers FS1267, Cornell High Tunnels greens and winter-greens disease pages, UKY CCD-SP-2, Penn State High Tunnel Production, Johnny's protect-crops page, 2021 row-cover chart, and 2015 Agribon insert, plus the High Tunnel System Initiative FAQ, Pennsylvania seasonal high tunnel, and CPS 325. Featured Amazon prices copied the same night. A missing featured price stays an em dash. Ratings are not copied. Seller frost or pest lines stay labeled seller claims. This page does not invent a USDA dollar, a °F gain, or a house takeoff.

Kit index: commercially manufactured kits. Replacement-parts directory: high-tunnel replacement parts. Winter lettuce (crop notes): high-tunnel winter lettuce. Heat: heaters / frost cloth. Alternatives: low tunnel / caterpillar / hobby. Insect netting: exclusion mesh. Fans: HAF / exhaust / thermostats. Thermometers: temperature monitoring. Scouting: pest control / IPM. Size map: high-tunnel sizes. County inspection: EQIP checklist. What the program will not pay for: EQIP will not pay for. Affiliate method: about / disclosure.

Figure: schematic hoop with inner low hoops, floating frost cloth, edge weights, and a sunny-day pull-back. Not a product photo.

Double cover: frost cloth inside the film

The house plastic is the first cover. A second, lighter sheet over the bed is the inner cover. Extension pages call that a secondary cover, a floating row cover, or a frost blanket. Those are their words, not a SKU mandate.

A secondary cover, often called a row cover or frost blanket, is made from lightweight material and placed over a row (or multiple rows) of plants. Mimicking the high tunnel’s ability to capture heat, the air beneath a secondary cover can be a few degrees (~2-5°F) warmer than the ambient air inside the high tunnel.
Source: University of Arkansas System Division of Agriculture — High Tunnel Production Guide for Arkansas and the Southeast (MP586; PDF opened 23 October 2026). The ~2–5°F line is UAEX’s. Do not turn it into a Tunnel Spec gain.

High-tunnel growers often use a tunnel-within-a-tunnel method to get plants off to a fast start or to maintain production of cold-weather crops such as spinach and greens throughout the winter. The use of floating row covers or low tunnels can greatly improve cool-season crop production by trapping heat directly in the crop canopy versus having the heat escape into the full tunnel.
Source: Penn State Extension — High Tunnel Production (updated 13 March 2023; opened 23 October 2026). Johnny's: Row covers can also be used inside high tunnels for an added layer of protection for overwintered crops. For example, we use a layer of Agribon+ AG-70 over many of our overwintering high tunnel flower crops. Source: Johnny's Selected Seeds — Protect Your Crops • Basic High & Low Tunnel Components (opened 23 October 2026). Purdue HO-297 scope: This publication primarily covers unheated high tunnels and the use of internal row covers. In the Midwest, cool-season crops are grown in these structures from about September through March. Crops include leafy greens such as kale, chard, lettuce, mustard, and spinach; head-forming brassicas such as bok choy; and root crops including radishes and turnips.

Weights — 0.5, 0.9, and 1.5 oz per square yard

Row covers can come in different thicknesses (0.5 – 2.0 oz/sq. yd), with thicker covers offering more frost protection than a thinner fabric. Any secondary cover will reduce the amount of light available to plants with heavier fabrics reducing light more than a lighter fabric. A thicker frost cloth can reduce available light by 50 percent or more.
Source: University of Arkansas System Division of Agriculture — High Tunnel Production Guide for Arkansas and the Southeast (MP586; PDF opened 23 October 2026). A second layer: Remember that the second layer of row cover will not double the protection achieved by the first cover, but will provide an additional degree or two of heat retention at the canopy level.

All harvest ranges assume that the grower would use at least medium-weight row cover over beds within the tunnel when nighttime temperatures drop below 25°F and double layer cover if nighttime temperatures drop below 10°F.
Source: Purdue Extension HO-330-W — High Tunnels: Scheduling Fall and Winter Vegetable Production (Maynard and Hilfinger; PDF opened 23 October 2026). HO-297 night rule on a single-layer house: Row covers are used at night when outside temperature goes below 25°F, and a second (or heavier) row cover may be added if the temperature goes below 20°F. DLI table used on the other date a lightweight (0.55 oz./sq.yd.), spun-bonded polyester row cover was over the plants for the entire day. Result: Without a row cover, DLI at plant level averaged 72% of outside DLI. With a row cover, DLI at plant level averaged 48% of outside DLI. Keeping the row cover on all day reduced light available to plants by about 1/3. Heavier vs light: Row covers come in different weights: heavier ones provide more insulation but block more light if they are left on during the day.

To address this, we compared temperatures in two beds inside a high tunnel—one covered with a 1.5 oz/sq.yd (Agribon AG-50) row cover placed on a wire hoop, and the other left uncovered—over two winters at the Southwest Purdue Agricultural Center. For example, when the minimum temperature inside the high tunnel was near 0°F, the row cover increased temperatures by approximately 12°F. However, when the minimum temperature inside the high tunnel was around 50°F, the row cover had little to no effect on raising the temperature.
Source: Purdue University Vegetable Crops Hotline — How Much Warmth Row Covers Provide at Extreme Cold Nights? (opened 23 October 2026). The 12°F near 0°F and “little to no effect” near 50°F are Purdue’s two-winter comparison of 1.5 oz/sq.yd AG-50 on a wire hoop — not a Tunnel Spec multiplier. Lettuce caveat: When used inside high tunnels, row covers clearly provide significant protection on extremely cold nights. However, this protection may not be sufficient for less cold-hardy crops like lettuce, which could suffer damage when temperatures drop to 28°F.

Agribon+ AG-19: 2–4° frost protection; 0.55 Oz. Per Sq. Yd.; 85% light transmission. Agribon+ AG-30: 4–6° frost protection; 0.9 Oz. Per Sq. Yd.; 70% light transmission. Agribon+ AG-50: 6–8° frost protection; 1.5 Oz. Per Sq. Yd.; 50% light transmission. Agribon+ AG-70: 8+° frost protection; 2.0 Oz. Per Sq. Yd.; 30% light transmission.
Source: Johnny's Selected Seeds — Row Covers Comparison Charts (copyright 2021; PDF opened 23 October 2026). Vendor table, not a land-grant trial. AG-15 on that same PDF: Unlike other Agribon weights, AG-15 does not provide protection from frost. That insect-barrier grade stays on insect netting.

Low hoops, clips, and edge weights

Row covers are often suspended above the plants using hoops or other means, but they can also be placed directly on the plants (Image 5.11). Under extremely cold temperatures, row covers placed directly on top of plants can freeze to the plants. Removing these row covers while they are still frozen to the plants can cause significant damage as well.
Source: University of Arkansas System Division of Agriculture — High Tunnel Production Guide for Arkansas and the Southeast (MP586; PDF opened 23 October 2026). UKY: Row covers used in conjunction with the high tunnel will provide additional cold and frost protection. Because row covers also block sunlight, they should not be left on for prolonged periods during the winter. Placing the row covers over hoops will help to keep tender leaves from freezing to the fabric. Source: University of Kentucky Center for Crop Diversification CCD-SP-2 — High Tunnel Overview (PDF opened 23 October 2026). Cornell: Medium-weight row cover supported on hoops gives 5-10 F warmth, more on colder nights. Purdue HO-297 hoop sentence: Row covers are another important means of reducing heat loss. These are typically lightweight, breathable fabrics placed over one or more beds or rows, sometimes resting directly on the crop, and sometimes supported slightly above the crop using hoops or frames of wire or conduit (Fig. 8). Condensation as insulation: They provide additional insulation around the plant, trapping heat near the plants as it radiates from the soil. When moisture condenses on the row cover, the insulating effect increases.

Unroll and place directly over transplants or planted seeds for “floating” installation or over #9 Support Wire, Hoop Loops, or Quick Hoops™ to create a low tunnel environment. To anchor, secure with Snap Clamps, Row Cover Hand Pegs, sand bags, or dig a furrow along each side and cover the fabric edges with soil.
Source: Johnny's Selected Seeds — Agribon+ AG-19, -30, -50, and -70 Row Covers insert (REV 12/09/2015; PDF opened 23 October 2026). Snap-clamp ASINs below are pack sizes. Sand-bag and hand-peg listings opened tonight did not return a featured one-time price.

Pull it on sunny days — light, heat, humidity

But those covers must be removed during the day for light transmission.
Source: Cornell High Tunnels — Greens (structures, cultural practices, winter hardiness; opened 23 October 2026). Dead-of-winter hardy under cover: These greens are generally hardy in tunnels under row covers without heat in the dead of winter: Spinach, Mache, Claytonia, Minutina, Tat soi and some other Asian greens. Lettuce is on the late-fall / early-spring list, not that winter list.

Even with a lightweight row cover, removing it during the day can increase the light to the crop. In the morning as temperature in the tunnel rises above freezing, row covers can be removed. The tradeoff is that the row covers left on during the day reduce light that the plant could use for photosynthesis, reduce the amount of the sun’s energy stored as heat in the soil, and maintain higher relative humidity near the plants.
Source: Purdue Extension HO-297-W — Managing the Environment in High Tunnels for Cool Season Vegetable Production (PDF opened 23 October 2026). Sunny-day heat: If a clear row cover is left in place on a sunny day, it can get too hot for the crop. The air temperature can go from below freezing to over 80°F in just a few hours. Vent: It is important to be prepared to vent the tunnel to keep temperatures below 80°F. HO-330: For single-harvest crops (beets, carrots, radish/ specialty turnip, head lettuce and scallions), the harvest range provides an estimate of the length of time in which the crop can remain in the ground and still be marketable, assuming that row cover is used according to the above guidelines and high tunnels are vented so as to not allow temperatures above 80°F. Johnny's insert: Remove if temperature exceeds 90°F/32°F under the row cover. That 90°F/32°F pair is the printed insert line — not a conversion we invented.

Condensation and disease

Floating row covers can be used to protect the plants from temperature fluctuations. Row covers used inside a high tunnel add additional insulation to the crop. However, careful consideration should be given when using row cover, as this will reduce airflow around the crop and increase the chances of foliar disease. Row covers will also reduce light intensity.
Source: Melendez — Ultra-Niche Crops Series: High Tunnel Winter Lettuce (Rutgers NJAES FS1267; opened 23 October 2026). Keep leaves dry: Lettuce leaves should be kept as dry as possible to reduce the incidence of foliar disease such as gray mold, and lettuce drop.

It is especially important to make sure leaves are dry after watering before placing row cover over plants. When using row covers, do not place over wet plants. Some occurrences of downy mildew in high tunnels have been associated with covering spinach when leaves were wet from watering.
Source: Cornell Vegetables — Diseases Occurring in Winter Greens and their Management (opened 23 October 2026). Vent: Vent high tunnels as often as temperature permits; but realize when open while field-grown crops are present, spores can move outside from an infected crop inside and vice versa. Cornell greens humidity: Powdery mildew on lettuce is a big problem under low light and high humidity conditions in late fall and early winter. (Lettuce is usually not hardy through the dead of winter.) Sticky cards and a 10× lens stay on high-tunnel pest control.

Not a caterpillar, not insect netting

Inner hoops under the film are still inside a walk-in manufactured kit. A field low tunnel or caterpillar is the house. Johnny's AG-15 / ProtekNet is mesh, not frost cloth.

The practice does not include greenhouses or low tunnel systems.
Source: NRCS Conservation Practice Standard 325 High Tunnel System. Outdoor low-tunnel and caterpillar SKUs stay on high tunnel alternatives and caterpillar vs high tunnel. SWD 80-gram sidewall ratings stay on high-tunnel insect netting.

Sourced Amazon row-cover parts

Titles and featured one-time prices were copied from live amazon.com product pages 23 October 2026, about 03:20 UTC. Kit frames stay on manufacturer product pages. Skipped tonight: B08G1VWTPZ 0.9 oz 6×50 (bot challenge); hoop packs B00IHKFA9Q / B00C9N3H6K / B07DC63JKC / B079KQJSCW / B08KD651SY (blocked or no featured); sandbags B09YXX8T9Q / B0BF1CXPD3 / B0CH15HVX6 (blocked); garden pins B08C78BB9L / B09S37Z3Z1 (blocked); B00C3YCDF6 resolved as EMT one-hole straps, not fabric pins.

Amazon Associate disclosure. As an Amazon Associate, we earn from qualifying purchases.

Kind	Pack	Listing	ASIN	USD
0.55 oz frost blanket	5×25 ft · 0.55 oz	Agfabric Plant Covers Freeze Protection 5'x25' 0.55oz Frost Blankets for Plants Plant Frost Protection Covers Garden Winter Frost Pests ProtectionFirst featured a-offscreen $11.99. Purdue HO-297’s DLI table used a 0.55 oz./sq.yd. lightweight cover left on all day. Pack size only — not a house takeoff. Seller frost/pest copy is seller claim, not a °F table.	B01BU13PJK	$11.99
0.9 oz floating row cover	12×25 ft · 0.9 oz	Agfabric Plant Covers Freeze Protection Floating Row Covers 12'x25' 0.9oz Plant Covers Freeze Sun Protection,Frost Cloth for Vegetables,WhiteFirst featured a-offscreen $12.99; other one-time prices on the same PDP included $23.99 / $25.99. UAEX names 0.5–2.0 oz/sq. yd; Johnny's 2021 chart lists AG-30 at 0.9 oz (vendor table). Pack size only.	B01G4QK666	$12.99
1.5 oz frost cover	7×50 ft · 1.5 oz	Agfabric Plant Covers Freeze Protection Row Covers 1.5oz 7'x50' Frost Cover for Freeze Protection,Frost Blanket for Plants,WhiteFirst featured a-offscreen $25.99. Purdue Hotline compared 1.5 oz/sq.yd Agribon AG-50 on a wire hoop inside a high tunnel. Pack size only — not a Southwest Purdue takeoff.	B00TQT9LC4	$25.99
3/4-in snap clamps	10-pack · 3/4 in EMT / 1/2 in Sch 40 PVC	Bootstrap Farmer Snap On Clamps 3/4 inch 10 pack Row Cover Clips for Greenhouse Plastic Shade ClothFirst featured a-offscreen $14.99. Johnny's 2015 insert: secure with snap clamps, hand pegs, or sand bags. Inner-hoop clip, not a house bow. Pack size only.	B07BJ1G6KC	$14.99
1/2-in snap clamps	10-pack · 1/2 in EMT	Bootstrap Farmer Snap On Clamps 1/2 inch 10 pack Row Cover Clips for Greenhouse Plastic Shade ClothFirst featured a-offscreen $14.99. Same Johnny's snap-clamp sentence. Match the clamp to the hoop OD — this is the 1/2-in EMT pack. Pack size only.	B072K1FWNY	$14.99
Stainless row-cover clips	60-count · 2.3 in · 1/2–1 in hoops	Samhopo 60 Pack Garden Clips for Greenhouse Netting, 2.3 Inch Metal Clamps \| Stainless Steel Body and Spring, Strong Grip Fits 1/2, 3/4 and 1 Inch PipeFeatured priceAmount $11.39. Seller netting/greenhouse copy is seller claim. Johnny's insert also names hand pegs and sand bags — those ASINs had no featured one-time tonight. Pack size only.	B0B5ZN96NK	$11.39

EQIP pays for the structure, not the cloth

Frost cloth, inner hoops, snap clamps, pegs, and sandbags sit outside the High Tunnel System Initiative payment. Confirm with your NRCS district conservationist. Tunnel Spec does not invent a dollar.

Under the High Tunnel System Initiative, financial assistance is provided only for the structure itself. Electricity, venting systems, lighting, etc. can be installed providing the additions meets manufacturer’s designs and specifications. However, the grower is responsible for those costs.
Source: USDA NRCS High Tunnel System Initiative FAQ (Updated November 2024; Oregon-branded). That PDF is silent on frost cloth, inner hoops, clips, and sandbags.

Producers can install heating, ventilation, or electrical systems at their own expense.
Source: USDA NRCS Pennsylvania — Seasonal High Tunnel System for Crops. One state office page, not a national row-cover payment. More exclusions: what EQIP will not pay for.

Rules vary; call your county NRCS office.

FAQ

Does EQIP pay for row cover, hoops, clips, or sandbags?: The High Tunnel System Initiative FAQ says financial assistance is provided only for the structure itself; the grower is responsible for electricity, venting, lighting, and similar additions. Frost cloth, inner hoops, snap clamps, pegs, and sandbags sit with those grower costs. Pennsylvania’s seasonal high-tunnel page says producers can install heating, ventilation, or electrical systems at their own expense — same structure-only split. CPS 325 says the practice does not include greenhouses or low tunnel systems. Inner cloth on hoops inside a funded house is still not a row-cover payment. This page does not invent a dollar. Confirm with your county NRCS office. See what EQIP will not pay for.
What weight row cover inside a high tunnel — 0.5, 0.9, or 1.5 oz?: Only the figures the pages printed. UAEX MP586: 0.5–2.0 oz/sq. yd; thicker covers offer more frost protection; a thicker frost cloth can cut light 50 percent or more. Purdue HO-297 used a 0.55 oz./sq.yd. cover for its all-day DLI table (72% of outside DLI without cover vs 48% with it). Purdue HO-330 assumes at least medium-weight cover below 25°F and a double layer below 10°F. Purdue Hotline compared 1.5 oz/sq.yd Agribon AG-50 on a wire hoop. Johnny's 2021 vendor chart (not a field trial): AG-19 0.55 oz / 2–4° / 85% light; AG-30 0.9 oz / 4–6° / 70%; AG-50 1.5 oz / 6–8° / 50%; AG-70 2.0 oz / 8+° / 30%. AG-15 is named as no frost protection — that is insect barrier, not this page. Those numbers stay labeled. Amazon packs on this page are sizes only.
Do I float row cover on hoops or lay it on the crop?: Both appear on fetched pages. UAEX: often suspended on hoops, but they can also rest on the plants; cloth frozen to leaves can tear plants when you pull it. UKY: place covers over hoops so tender leaves do not freeze to the fabric. Cornell: medium-weight cover supported on hoops, 5–10 F, more on colder nights. Purdue HO-297: sometimes on the crop, sometimes on wire or conduit hoops; moisture condensing on the fabric increases insulation. Penn State: floating row covers or low tunnels trap heat in the canopy. Johnny's 2015 insert: float on the crop or over #9 wire / hoop loops / Quick Hoops; anchor with snap clamps, hand pegs, sand bags, or a soil furrow. Inner hoops inside a walk-in house are not a field low tunnel and not a CPS 325 practice.
When do I pull row cover on a sunny day?: Cornell: covers must be removed during the day for light transmission. Purdue HO-297: even a lightweight cover left on all day cut DLI by about one-third; remove it during the day to increase light; in late fall/winter pull it once the tunnel is above freezing; leaving it on cuts light, soil-heat storage, and raises humidity; a clear cover left on a sunny day can get too hot; vent so the house stays below 80°F — air can go from below freezing to over 80°F in a few hours. Purdue HO-330 vents so as not to allow above 80°F. UKY: do not leave covers on for prolonged periods in winter. Johnny's 2015 insert: remove if temperature exceeds 90°F/32°F under the cover — that paired figure is Johnny's printed line, not a Tunnel Spec conversion. Purdue Hotline: a 1.5 oz cover on hoops added about 12°F when the house was near 0°F and almost nothing near 50°F. Those are the printed sentences.
Does inner row cover cause condensation and disease?: Rutgers FS1267: inner row cover adds insulation but reduces airflow and increases foliar-disease chance, and it reduces light; keep lettuce leaves as dry as possible (gray mold, lettuce drop). Cornell greens: powdery mildew on lettuce is a big problem under low light and high humidity in late fall and early winter. Cornell winter-greens disease page: do not put row cover over wet plants; some high-tunnel downy mildew on spinach was associated with covering wet leaves; vent as often as temperature permits. Purdue HO-297: condensate on the fabric increases insulation — and leaving cover on all day maintains higher humidity near the plants. This page is not a spray schedule. Pest cards stay on high-tunnel pest control.
How is this different from a caterpillar / low tunnel or insect netting?: A field low tunnel or caterpillar is a stand-alone short house. CPS 325 says the practice does not include greenhouses or low tunnel systems; a funded high tunnel still has to be a manufactured kit at least 6 feet at the peak. Inner frost cloth on low hoops inside that kit is a secondary cover — UAEX, Penn State, Johnny's, and Purdue describe it that way. The caterpillar / alternatives pages own the outdoor low-tunnel SKU race. Insect netting is a different fabric. Johnny's 2021 chart: Agribon+ AG-15 does not provide frost protection; ProtekNet is exclusion mesh. SWD 80-gram sidewall ratings stay on high-tunnel insect netting. Do not treat frost cloth as exclusion mesh or a low-tunnel kit.

Rules vary; call your county NRCS office. Tunnel Spec does not determine eligibility, payment rates, or inspection outcomes. Not a planting calendar and not a °F table. As an Amazon Associate, we earn from qualifying purchases.