How and When to Harvest

Keep Plants Producing with Frequent Harvests

If you are a Northeast grower like us, July is a good time to take stock of the current situation in your vegetable garden. In mid-summer, plants are usually in their prime, but look closely and you might find the beginnings of an insurrection—perhaps in the form of a sudden onslaught of slugs nibbling or fungi forming after a few days of otherwise much-needed rain. Look closer still and notice the steady march of Japanese beetles, aphids, whiteflies, and cabbageworms arriving like hungry guests to a banquet hall. As you survey your beds and begin prioritizing the various tasks ahead, the garden may appear to have shifted shape as some crops lose steam and others gain ground. Is it time to pull up the peas, you wonder, and plant pole beans in their place? While there is much to decide and attend to in the garden, don’t forget the best part: the harvest!

To maximize your plants’ productivity, harvest you must. And we have a few tips to help make harvesting a habit. 

First things first
Harvest from your garden frequently—even daily—if you can. Regular gleanings will stimulate plants to produce more leaves for photosynthesis and more fruit for reproduction—all to your benefit. Midday heat can be taxing on plants, so aim to make your snips and snaps in the cooler hours of morning or evening. By harvesting frequently, you’ll also be less likely to have to clean and store an enormous amount of produce all at once.

If you are feeling particularly organized, set up a “harvest processing station” in your kitchen with strainers, towels, a salad spinner, twine for drying herbs, and containers for storage. See here for storage and preservation tips.

One of the easiest ways to form a harvesting habit is by keeping your favorite tool alongside an empty basket, trug, or mixing bowl in a dedicated spot that will remind you to go out to pick and pinch your plants. With these trusty sidekicks always within reach, it will be easier to multitask as you address the ongoing developments within the garden.

As you harvest, clean up any weakened or yellowing leaves. Plant debris can be turned under with a hand hoe or placed in a compost pile (but anything that looks diseased should be removed and placed into your garbage rather than into your compost bin). Clearing debris will also promote good air flow which helps crops defend against black spot, blight, mildew, and rust diseases.

Scan the list below for some helpful hints on harvesting specific crops:

Leafy Greens
Cut-and-come-again lettuces can provide several weeks of continual harvests. Simply pick from the base upward or cut straight across--but avoid cutting the central crown where the newest leaves are formed. Allow leaves to lengthen to about four inches between gleanings. When lettuce leaves begin to swirl upward from the center, they are about to bolt and turn bitter; at this stage, either harvest the entire head or let it go to seed.

Brassicas
Cabbages like fertile soil with even moisture levels. As your crop grows, remove any caterpillars, cabbage moth eggs, and leaves infiltrated by cabbageworms. Before lopping off your cabbage heads, make sure they feel firm and dense. Late season cabbages taste even better after they’ve been nipped by a few light frosts.

Broccoli heads should be cut when they are firm, before the tiny yellow flowers of their inflorescences open. After the main head has been cut, broccoli will send out a succession of smaller spears for continual harvest.

Kale can be harvested from the bottom up to create a palm-tree like shape; new leaves will form form from the top of the plant. You can also provoke kale into sending off side-shoots if you choose to pick from the youngest leaves at the top.

Legumes
Peas have shallow root systems, so be gentle when you snap pods from their stems or just use a pair of snips. An overzealous plucker can unwittingly pull an entire plant from the ground. And know what kind of peas you are growing—are they shelling peas or snap peas? Snap peas and snow peas taste best when the pods are slightly immature and can be eaten whole, whereas a shelling variety will want more time to plump up before plucking.

Pole beans produce better yields if they are kept evenly watered during flowering. Depending on the variety you’ve sown (beans have a wide range of lengths), harvest mature pods by carefully tugging them downward.

Bush beans are less sensitive to dry spells during flowering. Pluck pods when they are still firm and snap easily. If you allow pods to mature on the plant, you will have a poorer overall yield, so harvest regularly.

Alliums
Onions
need room to develop their bulbs as they grow; to give them space, thin younger, crowding bulbs for eating fresh. When the leaves of mature bulbs yellow and topple over, the bulbs themselves are done developing and you can pull them from the ground.

Garlic
leaves, like onion leaves, will yellow and topple over when the bulbs are mature and ready to be eased with a garden fork or spade from the ground. You’ll have more luck curing and storing your garlic and onions if you can harvest them when the surrounding soil is relatively dry.

Roots 
Carrots will come up more easily if you soak the ground first. You can also gently loosen the surrounding soil before attempting to pull them up. If you want to check to see if carrots are ready, you can take a “sneak-peek” by brushing the top layer of soil from their shoulders. If they are too small for your liking, simply replace the soil.

Beets need space for their bulbs to mature; thin according to the spacing designations of your variety. Water during dry spells to help swell roots and leaves. While the bulb matures, you can regularly harvest the foliage—as long as a few leaves are left for the plant to perform photosynthesis.

Turnips and Kohlrabi are brassicas grown primarily for their crunchy, delectable roots. Like other brassicas, evenly moist and fertile soil will produce the best harvest. Plants that become too dry will develop woody-textured roots that are unpleasant to eat. As the roots develop, you can trim leaves for salads and sautés just as you would for beets. Harvest turnips and kohlrabi when their roots are about the size of a golf-ball are slightly larger.

Fruiting Vegetables
Summer squash plants should be checked frequently for harvesting the tender, mild-tasting fruits; if allowed to mature and develop their seed, then your plants will have less incentive to produce more fruits. Harvest by cutting the stem above the fruit with a sharp knife.

Winter squashes, unlike summer squashes, improve in flavor and color when left to fully mature on the vine. To check for ripeness, look for woody stems near the fruit; a deep, rich hue to the skin; and a hollow sound when knocked.

Cucumbers benefit from regular watering and will stay productive for longer when fed with a balanced fertilizer after they first flower. Inspect plants frequently to harvest the fruit; if fruit is allowed to mature on the vine, the plant will be less productive. Gently tug the cucumbers to release them from the vine, or use a knife.

Peppers can be harvested and eaten when they are still quite firm and green, but leave them on the plant to develop and soften a bit and you will have a pepper with more “personality” and distinctiveness of flavor. Depending on the specific variety, peppers can turn yellow, red, orange or purplish-black at their most mature. Tugging the fruit can result in breaking off too much of the plant, so opt for a knife or garden shears when you go to harvest. 

Tomatoes mature to a range of colors, like peppers, although most varieties end up red. Depending on the variety you are growing, your mature tomatoes can be pale yellow, orange, green, reddish-brown, purplish-black, or striped. If plucked at an immature stage when they are still quite firm to the touch, tomatoes will still ripen off the vine (at room temperature, away from sunlight). But to harvest your tomatoes at their peak, allow them to develop their flavor on the vine. Ripe tomatoes will feel only slightly firm, with thin skin that easily bruises. Tug tomatoes above the calyx to promote more production of fruit.

Sweet Corn
Corn ripens from the top down, so start with the topmost ear when you go to pluck. Corn is ready when cornsilk tassels turn brown and shrivel back toward the cob. If pierced with a thumbnail, ripe kernels will release a milky-white juice. Collect cobs by twisting and yanking downward. Once harvested, corn should be eaten as soon as possible; the sugars in the kernels will turn starchy the longer you wait.

We hope these little harvesting hints will inspire you to get out into the garden to provoke your plants into further production. For more in-depth coverage of vegetable crops and other gardening topics, like what seeds to sow now for your fall harvest, just use the search bar on our blog page.


Happy Harvesting!