Summer-Harvest Broccoli on Ice

CHART • Post-Harvest Handling & Storage of Summer Produce

Keep Your Summer Harvest at Peak Eating Quality

Once harvested, crops can quickly deteriorate in the summer heat. Whether you bring your vegetables to your own table or to market, you'll want to cool and store them quickly so they retain their appearance, flavor, and nutrient profile. Use this chart as a quick reference to cooling methods, temperature ranges, relative humidity, and approximate length of time vegetables can be held.

Note that these figures are approximate, and the methods are simply those in general common use in the US during warmer months of the year. There is no single right way to handle the harvest of a particular crop, so you will want to adjust your practices to the conditions at hand. The many variables to consider include quantity, size, and maturity of crop; the scale of your operation; time, labor, and equipment resources; microclimate; conditions at harvest and time of day; whether or not you plan to transport your produce; and how long you expect the particular crop will be stored before it is enjoyed.

Also keep in mind that just as the sun, wind, and heat of the field or greenhouse can quickly damage a fresh crop, so too can chilling injury occur at temperatures below optimum storage temperatures — even, in some cases, 10–20°F above freezing. Furthermore, both heat damage and chilling damage are cumulative.

Keep Cool & Build Your Own
CoolBot Video
Jean–Martin Fortier on how to use the CoolBot PRO
For small-scale growers needing an easy cooling solution, we offer the CoolBot, an instrument that turns an off-the-shelf air conditioner into a walk-in cooler compressor.

The CoolBot PRO is a wi-fi enabled version you can control via a portable tablet or cell phone.

In this video, award-winning author, educator, and four-season market-gardener Jean–Martin Fortier gives us a tutorial on using the CoolBot PRO to set, monitor, and adjust your cool-room temperatures using your mobile device.
COOLING & STORAGE CHART • Summer Vegetable Crops
CROP TYPE PREFERRED COOLING METHOD
Click for Keykey
OPTIMUM TEMPERATURE (T) FREEZING/ CHILLING DAMAGE T * RELATIVE HUMIDITY STORAGE POTENTIAL
ARTICHOKE Globe RC
FAC
32°F / 0°C 30–31°F / -1.1 – -0.6°C 95% 14–21 days
ASPARAGUS   HY 32–36°F / 0–2.2°C 30.9°F / -0.6°C 95–100% 14 days
BEANS Bush, Pole & Snap Varieties FAC 40–45°F / 4.4–7.2°C 31°F / -0.6°C 90% 7–10 days
  Lima/Butterbeans & Fava Varieties HY preferred; FAC alternative 37–41°F / 2.8–5°C 31°F / -0.6°C 95% 5–7 days
BEETS Baby Beets & Greens

For Full-Size Varieties, see Fall–Winter Storage-Crop Chart
FAC, HY, IC 32°F / 0°C 30–31°F / -1.1 – -0.6°C 95–98% 7–10 days
BROCCOLI Standard, Leaf, Raab, & Sprouting Varieties HY, IC 32°F / 0°C 31°F / -0.6°C 95–98% 10–14 days
BRUSSELS SPROUTS See Fall–Winter Storage-Crop Chart          
CABBAGE Fresh-Market, Early & Main Season, & Chinese Cabbage Varieties

For Storage Varieties, see Fall–Winter Storage-Crop Chart
RC, FAC 32°F / 0°C 30°F / -1.1°C 95–98% 10–90 days
CARROTS Early & Main Crop Varieties

For Storage Varieties, see Fall–Winter Storage-Crop Chart
RC, HY 32°F / 0°C 30°F / -1.1°C 95% 28 days
CARDOON   HY 32°F / 0°C 31°F / -0.6°C 98–100% 14–21 days
CAULIFLOWER   HY 32°F / 0°C 30–31°F / -1.1 – -0.6°C 95–98% 14–21 days
CELERY Stalk

For Celeriac/Celery Root, see Fall–Winter Storage-Crop Chart
HY 32°F / 0°C 31°F / -0.6°C 98–100% 30–60 days
CHICORY Endive, Escarole, Radicchio, & Italian Dandelion Varieties HY, IC 32°F / 0°C 30°F / -1.1°C 95–100% 14–28 days
COLLARDS   RC, HY, IC 32°F / 0°C 30°F / -1.1°C 95% 7–14 days
CUCUMBERS   FAC, HY 45–50°F / 7.2–10°C 31.1°F / -0.5°C 90% 14 days
EGGPLANT   RC, FAC 50–54°F / 10–12°C 30.6°F / -0.8°C 90–95% 7–10 days
FENNEL Bulb RC, HY 32°F / 0°C 30–31°F / -1.1 – -0.6°C 95% 21–28 days
GREENS,
Leafy
Arugula, Asian Greens, Mustard Greens, Pac Choi, Sorrel, & Specialty Greens HY, IC 32°F / 0°C 30°F / -1.1°C 95–100% 7–21 days
KALE   HY, IC 32°F / 0°C 30°F / -1.1°C 95–100% 14–21 days
KOHLRABI Fresh Eating

For Storage Varieties, see Fall–Winter Storage-Crop Chart
RC, HY, IC 32°F / 0°C 30.2°F / -1°C 90–100% 60–90 days
LEEKS See Fall–Winter Storage-Crop Chart          
LETTUCE   HY, IC (except Romaine) 32°F / 0°C 30°F / -1.1°C 95–100% 7–21 days
MELONS,
Cucumis
melo
Netted Varieties FAC, HY, IC 36–41°F / 2.2–5°C Risk of chilling injury below 35.6°F / 2°C 85–95% 5–12 days
See also
Melon Growing Guide
Smooth-skinned Varieties RC 45–50°F / 7.2–10°C Risk of chilling injury below 45°F / 7.2°C 85–95% 10–14 days
OKRA   FAC, HY 45–50°F / 7.2–10°C 28.7°F / -1.8°C 95–100% 7–10 days
ONIONS
Bunching/Green, Mini & Specialty Varieties

For Storage Varieties, see Fall–Winter Storage-Crop Chart
HY, IC 32°F / 0°C 30–31°F / -1.1 – -0.6°C 95–100% 21–28 days
PEAS,
in pod
Snow & Shelling Varieties HY, IC 32°F / 0°C 30.9°F / -0.6°C 95–98% 5–10 days
Snap Varieties HY preferred; FAC alternative
PEPPERS   FAC, RC 45–50°F / 7.2–10°C 31°F / -0.6°C 90–95% 14–21 days
POTATOES See Fall–Winter Storage-Crop Chart          
RADISHES   HY 32°F / 0°C 30.5°F / -0.8°C 95–100% Small:
7–14 days with tops;
21–28 days topped.
Large (eg, Daikon):
42–70 days
SPINACH   HY, IC 32°F / 0°C 31.5°F / -0.3°C 95–100% 10–14 days
SQUASH Summer (soft rind)

For Winter Varieties (hard rind), see Fall–Winter Storage-Crop Chart
RC, FAC 41–50°F / 5–10°C 31.1°F / -0.5°C 95% 7–10 days
SWEET CORN   HY, IC 32°F / 0°C 31°F / -0.6°C 95–98% Standard:
5–7 days; Super Sweet:
8–12 days
SWISS CHARD   HY or FAC preferred; RC alternative 32°F / 0°C 15–20°F / -9.4 – -6.7°C 95–98% 7–14 days
TOMATOES   RC, FAC For ripening: 68°F / 20°C
For storage: 45–60°F / 7.2–15.6°C
30.5–31.1°F / -0.8 – -0.5°C 90–95% 4–7 days
TURNIPS Summer Varieties HY, IC 32°F / 0°C 30°F / -1.1°C (roots) 95% 10–14 days with tops
WATERMELON
Citrullus
lanatus
var. lanatus
  HY, IC 45–50°F / 7.2–10°C Risk of chilling injury below 45°F / 7.2°C 85–95% 14–21 days

* Significant chilling damage can occur 10–20°F above freezing.

key   Key to Cooling Methods

RC = Room Cooling

The process of removing heat from freshly harvested produce within a closed space fitted with a mechanical cooling system, such as air conditioning.

FAC = Forced-air Cooling

Using pressure/fans to pull refrigerated air through freshly harvested produce to remove heat.

HY = Hydrocooling

The process of removing heat from freshly harvested produce by bathing it in ice water.

IC = Icing

The use of ice for cooling, either by package icing or by bulk application to the top of a load.