UPDATE: If you have not yet harvested seeds from your fall plants, then it may be time to do so now or soon. (Bean, artichoke, and chard plants will probably not be producing seeds at this time, however.)
If you are participating in our fall seed saving program, some of your plants may have gone to seed by now. Here is a guide to harvesting the seeds:
➤Arugula – Seed heads will turn a pale sandy brown (beige) and brittle when mature. Eventually, they will split open. Try to harvest them before they split; otherwise, take extra care so the seeds don’t fall from the pods. Please note, a crop of arugula can produce seeds gradually, for a few weeks to almost a month. You may want to harvest seeds more than once. When a good amount of seed heads have matured, then seed stalks can be harvested, or the whole plant can be uprooted and hung upside down to dry in a space set aside for curing. (1)
➤Bean (Green, Bush) – Harvest pods when some have faded to pale yellow, and others are very dry and have split open. This is about a month and half after you would have harvested the beans to eat. Be very careful so the beans don’t fall from the pods. See ‘Arugula’ for note on repeat harvesting. Please also note – If any of your bean plants show signs of disease, do not save seeds from them, as the seeds may harbor the disease and/or be disease-prone. (1)
➤Broccoli – The little pods containing broccoli seeds ripen gradually, from the lower pods to the upper ones. “Wait until most of the pods turn light brown before picking,” even though you will probably lose some seeds from the lower pods as they split. (1) (If you harvest the pods at an earlier stage, before any of them split, then you may end up collecting mostly green pods, which contain immature seeds that are not viable.) Another option is to harvest the whole plant (or multiple plants) at this point and hang it (or them) upside down in your curing space to dry. (1)
➤Cilantro – Harvest the seed heads as they dry. Do so before the fruits shatter. (Each round, dry fruit contains two seeds.) (1)
➤Lettuce – Each individual lettuce plant may produce seeds for a period of a few weeks up to a month and a half, on a seed stalk that matures from top to bottom. “Professionals harvest when the seed stalk is in 50 percent feather (the white pappus is the ‘feather’)… [The seed stalk] can be “shake[n] into a bag to avoid loss from shattering.” (1) Or the whole plant can be uprooted and hung upside down to dry in a curing space.
Please note – If only a few of your lettuce plants have bolted (gone to seed) earlier than the rest, or if the whole crop went to seed quickly, avoid harvesting seeds from those plants, “or you will inadvertently be selecting for fast-bolting lettuce.” (1)
➤Parsley As each seed head starts to dry and turn brown, tie a paper bag over it, so you will catch the seeds instead of losing them when the heads shatter. Harvest seed heads after a few weeks when they are dry by cutting the stems below the paper bags. Leave the seed heads in the paper bags in your curing space to continue drying. Wait to clean them until they are perfectly dry. (1)
➤Pea – Harvest pods when they have turned pale sandy brown (beige) and brittle, and when you can hear the peas rattling inside. Or harvest slightly beforehand, when the pods have paled and some have started to turn brown. At this point, the whole plant can be uprooted and hung upside down in a curing space until the peas within the pods have dried.
Please note – If any of your peavines show signs of disease, do not save seeds from them, as the seeds may harbor the disease and/or be disease-prone. (1)
➤Radish Be selective when harvesting these seeds. The first stage of selection happens at the time when you would normally harvest the radishes to eat. Dig them up at this point and inspect them for qualities you prefer, such as size and shape, just as you would if you were shopping for radishes. Cut the leafy tops off your selected plants, about an inch above the roots, then replant them. Bury each one so all but the cut stem is covered with soil. Then wait to harvest until most of these plants have bolted and gone to seed. It is okay to miss out on harvesting the earliest seed heads– This is the second step of selection, selecting for late bolting. The seeds of early-bolting individuals should be avoided, because they will produce more plants that are not adapted to the climate of your growing space, and will continue to bolt early in future generations. Harvest each pod or stalk of pods when it is dry and brown, or harvest entire plants when they have dried somewhat, and hang them upside down in your curing space to continue drying. (1)
1 Gough, Robert and Cheryl Moore-Gough. The Complete Guide to Saving Seeds. North Adams, Massachusetts: Storey Publishing, 2011.
Updated 3/6/17 to include seed harvesting info for broccoli, parsley, and radishes. Images updated, too.