When and How to Harvest Pickling Greens: Cutting the Whole Plant

What a plant ready to cut looks like

Ready means large. A plant worth cutting stands eighteen to twenty-four inches (45 to 60 cm) tall with a rosette twenty inches (50 cm) or more across, and it takes sixty to eighty days from sowing to get there. The single most reliable indicator is not the leaf but the stalk: run your thumb and finger down the midrib of an outer leaf, and when it is broad, flat, crisp and roughly half an inch (12 mm) wide at the base, the plant has done what it is meant to do.

The second indicator is frost. Cold changes this crop substantially, converting starch in the leaves and stalks to sugar, softening the raw mustard bite and giving the stalks a sweeter, cleaner taste. Two or three hard frosts make a real and obvious difference. A plant cut before any frost is perfectly usable but noticeably sharper and greener in flavor than the same plant cut a fortnight later after cold nights.

So the harvest decision is a balance. Cut too early and you have a small plant with thin stalks and a raw edge. Wait too long into a hard winter and outer leaves start to tatter and rot at the base. The window in between, once the stalks are thick and a few frosts have passed, is several weeks wide in most gardens.

Cut the whole plant at the base

Slide a sharp knife in at soil level and cut horizontally through the stem just above the root, keeping the rosette intact so the whole plant lifts as one piece. That is the correct harvest for this crop, and it is how the plant is designed to come off: a compact bundle of long leaves held together at the base, easy to wash, easy to carry and easy to handle in the kitchen.

Picking outer leaves one at a time is possible and does no harm early on, but it is not how you get the crop. Repeated leaf picking keeps the plant small, and you never accumulate the mass of thick stalks that is the point of growing it. Take a few outer leaves as needed by all means, but plan for a whole-plant cut in the end.

Harvest at midday in freezing weather so the plant has thawed. Choose a dry day if you can, because leaves cut wet in cold conditions do not dry properly and go slimy in storage. Trim off the outermost ring of yellowed or damaged leaves in the garden rather than carrying them indoors, and leave them out of the bed if they are diseased or on the compost pile if they are simply old.

The root and the stump can come out at the same time. Leaving brassica stumps in the ground over winter keeps the family's pests and diseases going into the next season, so lift them, knock the soil off and check the roots while you have them in your hand.

1. Cut low and level Aim the knife just above where the leaves join, roughly half an inch (12 mm) above the root crown. Cut too high and the plant falls apart into loose leaves; too low and you take root that has to be trimmed out later.
2. Wash the base thoroughly Soil collects between the leaf stalks at the crown. Split the base slightly and rinse under running water, working outwards. Grit trapped at the base is the most common complaint about this crop and it is entirely avoidable.
3. Dry before storing Shake and drain the plant thoroughly, then let it sit somewhere airy for an hour before it goes into a bag. Wet leaves in a sealed bag turn slimy within two days; well-drained ones keep a week or more in a cold place.
4. Harvest in sequence, not all at once Cut the largest plants first and leave the rest standing. In cold weather the bed is the best possible storage, and a plant left in the ground keeps far better than one in a refrigerator.

Getting the timing wrong in either direction

Cutting early costs you weight and flavor but nothing else. A plant taken at three quarters size is a perfectly good vegetable, just a smaller and sharper one, and if the bed is needed or a severe cold snap is forecast beyond what the crop takes, cutting early is a sensible decision.

Leaving it too long is the more expensive error, and it has two forms. In a hard winter the outer leaves progressively tatter, freeze-thaw damage accumulates as brown patches, and slugs work into the base. The plant is still usable but you lose the outer third. In a mild winter the opposite happens: growth resumes as light returns, the plant switches to flowering, and the stalks turn tough and hollow at the center. Once you see the crown lifting and the newest leaves emerging narrow and upright, cut everything within days.

Neither failure is dramatic. The practical rule is that once the plants are at full size and a few frosts have passed, there is no advantage in waiting, and there is a slow accumulating cost.

Record the date of your first cut, the date of the last one, and roughly how many plants you actually used. Most gardeners grow far more of this crop than a household consumes, and one honest count turns next year's sowing from a guess into a decision.

Using and keeping the crop

A whole cut plant keeps five to ten days in a cold place if it went in dry, standing upright rather than lying flat. Wrapped loosely in damp paper in the coldest part of a refrigerator it will hold a week. Do not chop it before storing; the leaves keep much longer intact.

The thick stalks and the leaf blades cook at quite different rates, so separate them. Slice the stalks crosswise and give them two or three minutes head start in the pan before the leaves go in, and both come out right. Blanched for two minutes and squeezed dry, the leaves freeze well in portions for cooked dishes.

Salting is the traditional route for a large harvest and it is straightforward: whole washed plants layered with salt at roughly three to four percent of their weight, weighted down, and left in a cold place. The stalks stay crisp and the flavor deepens over a week or two. This is the reason to grow the plant large in the first place, since it is the stalks rather than the leaf blades that make the result worth eating.