How To Tell When Popular Vegetables Are Mature Or Ripe

We’re tantalizing close to peak harvesting time in the vegetable garden. From late July until October and beyond, we’ll be reaping the fruits and vegetables of our labors and from what I’m hearing and seeing it could well be a bumper year for home growers, though the excessive heat may cut down on tomato yields. But along with the harvest comes the age-old question, when is it ripe?

So this week we’ll take a look at how to determine when your crops are ripe and how to harvest them. But first, is it ripe or is it mature? Ah, that’s the second age-old question. The difference may be somewhat nebulous because produce that is ripe is, in fact, mature. But produce that is mature may not be ripe. Take for example the tomato.

Mature tomatoes can indeed be green. In this case they are not at all ripe and will taste rather foul if eaten, but at maturity a tomato can be harvested and over a period of time it will ripen and turn red, or kind of red. The best taste, though, comes from a vine-ripened tomato.

Not all fruits and veggies will ripen once picked. There are some technical standards for maturity, but if you’re not a produce manager or long-distance shipper your real concern is ripeness. I’ll simply define this as when the fruit or vegetable tastes best.

This is not to be confused with the seed packet information that says “Days to harvest.” That number should only be used as a guide of when to check for harvesting and as marketing tools they are usually optimistic in the day counts.

Time of day can also be critical when picking your veggies. Harvesting should be done early in the morning. The shelf life of produce is closely related to its respiration rate and that is directly related to the air and produce temperature. As the air warms and respiration rates increase, the shelf life of any given vegetable will be reduced.

Beans, especially the “string” and “snap” types, are harvested when they are young and tender. The seeds may be evident but should be small. If you leave the pods on the plants too long they get tough, coarse and woody, losing a great deal of their flavor. Again, check the information on the variety you planted to get a good idea how long the pods should be when reaching maturity.

Beets come in all shapes and sizes as well as colors. As a general rule, it’s the size of the beet that will be the best indicator of when it’s ready for harvest, and depending on the variety this can be anywhere from 1 to 3 inches in diameter. Always err on the side of smallness as larger and older beets get pithy and lose their sweet taste. The exceptions are varieties I refer to as “keepers” that mature later in the season and actually sweeten up after a frost or two.

Broccoli heads (or crowns) are harvested when the florets are tight and the color is a rich green. When the florets begin to stretch and loosen and the color begins to turn paler, the flavor changes as does the nutritional value of the harvest. As a rule, the diameter of the “terminal head” should be about 3 inches and harvesting should continue as new heads fill in and mature. Most broccoli will produce “replacement” heads as the season progresses, though subsequent heads may be smaller.

Carrots used to be simple to pick because there were only a handful of varieties. Now, however, there are multitudes of types, sizes and colors of carrots so you need to remember what varieties you have, what their growth characteristic are (blunt, short and thin, long and slender, etc.). The older standards can be harvested at about 4 inches in length and 3/4 of an inch in diameter. Baby types are harvested when about 3 inches long, and globe types when they develop the characteristic shape that’s visible at the soil surface. A finger pushed into the soil will reveal a lot of information.

Corn harvesting is a bit of an art and few of us have enough room at home to grow corn. But for those who do, sweet corn is ready when the silks have dried to a golden brown, the kernels are full and plump, and the ear well filled. Ears should be at least 5 inches long. Keep in mind also that corn is best fresh, like right after it’s picked, or it should be refrigerated in the husk until cooked. If you’ve grown supersweet or sugar-enhanced varieties, harvesting can be delayed for several days past the indicators.

The clues for cucumbers are size and color. Slicer types should be straight, at least 6 inches long and no bigger than 2 3/8 inches in diameter. Pickling types will be shorter and smaller in diameter unless they are Kirbys. Color should range from light to dark green, and yellow usually indicates over-ripeness except for the “lemon” varieties. Cukes are great at hiding and showing up when they are too large so search carefully and often.

For cabbages, pay attention to the “days to harvest” information as one guide. Head firmness is the best indicator but also know what the head diameter should be for the varieties you’re growing. Cabbage heads that split can still be harvested but they won’t store well.

Cantaloupe or muskmelon stems “slip,” or naturally break, when the melons are ripe. Other indicators are a slight softening at the blossom end of the melon, aroma, change in the color of the netting areas from green to yellow and the netting itself turning toward yellow. Non-slip melons can be tested by aroma and rind color while watermelons can be thump tested — but that’s an even more intricate art. Ripe watermelons also have a characteristic yellowing at the “ground spot.”

Eggplants are harvested when the color is right and the “skin” conditions are bright and shiny. Remember that there are many kinds of eggplants, so know how long your variety should be when mature and what the characteristic color should be. You’ll wait a long, long time for a white eggplant to turn deep purple. Asian eggplants are generally smaller and tear drop in shape while some heirlooms can be as small as grapes.

Garlic (hard types) are planted in the early fall then not harvested until late the following summer. This makes it one of our longest veggie crops. Garlic will give you a hint when it’s ready to harvest when about half the leaves have turned brown and the balance are still green. Stop watering the plants about a week before harvest so the soil is dry and use a garden fork or your hands to harvest. Don’t pull them but try to get your fingers under the clove then gently lift it. Do not wash the bulbs or remove the paper-like coverings. Hang and store in a warm dry place.

Onions, mostly the globe type, can be harvested at any point when they are needed during the summer. But when you plan on storing them, as in dry, they are harvested when the tops begin to fall over.

Peppers, both green bell and hot types, should be dark to light green and uniform in color. Red and colored peppers should be uniform in color as well and for all types the lobes should be well formed and should feel firm and heavy when lightly squeezed. Bell peppers should be no less than 2 ½ inches in diameter and length. Leaving hot peppers on the stem longer, past their maturity, will not increase their hotness.

Potatoes give a signal when they’re ready to harvest. Their tops die down. About two weeks after this happens you can dig them, and this delay gives their skins time to toughen if you want to store them. Some potatoes can also be left in the ground for weeks after they are mature.

Summer squash should be straight unless they are the crookneck or patty pan types. The rind should be bright in color and have a shine. Zucchinis and crookneck types should be no longer than 8 inches max, and 1 to 1 ½ inches in diameter. Many gardeners will harvest zucchinis anywhere from 2 to 6 inches, but watch out for those baseball bats.

Tomatoes can be harvested from their “mature” stage right through the pick-and-eat stage, so it pretty much depends on what your purpose is. You’ll need to do a bit of reading on your own here because some tomatoes can be picked and stored for weeks, some are harvested all at once and processed for sauces, canning and freezing while some will continue to fruit and ripen for four to eight weeks from the same plant. Keep in mind that determinate types will tend to ripen over a two-week period then the harvest is over. Indeterminates continue to flower and produce for weeks and weeks as the vines get longer.

Happy harvesting. Keep notes on successes and failures for next year. Keep growing.

So far it’s been a banner year for Japanese beetles, but it can vary from one area to another. The topic has been covered here a number of times, but if you need a refresher and if you need to know why traps shouldn’t be used, look at Margaret Roach’s piece in the New York Times from July 11.

The insecticide pyrethrum is considered to be very safe as well as organic. However, most formulations contain pypernol butoxide (PBO) which is a synergist that makes the pyrethrin work better. The PBO is NOT organic so products containing it cannot be certified organic. You can ask for non-PBO pyrethrin at local garden centers, and it can be found online.

Remember that some organic insecticides can kill everything they contact. That’s both the good and the bad bugs. Never use pyrethrin when bees are foraging and never use it on hot sunny days.

Have a plan for your fall veggie garden yet? Planting time is now and for the next few weeks. Garden centers have plenty of seeds and even some new seedlings in cells.