A favorite self-seeding annual...
Many seeds are really easy to collect and store. Annuals will generally grow and bloom again next year if you collect them now. Perennials may take a year or two to get established, so if you decide to collect and store or collect and plant them, make yourself some notes where they’ve gone into the ground, because you may not get blooms next year.
Here are some points to consider:
Seed Maturity: Collect mature seeds. If you don’t know if the seed is mature or not, wait a bit. If it gets dryer, browner, or starts to fall out, then it’s mature. You can cut off the entire seed head and then shake out or pick out the seeds. Here’s an example. Where I live, Lantana is an annual (I love visiting the south where they grow so huge). Lantana seeds start out green and mature to a deep purple/black color. I don’t collect them till they’re just about ready to fall off the plant. Marigolds are easier to tell; the flower drops off and the seeds grow and when they’re nice and dry, just nip ‘em off.
Some annuals, you’ve probably noticed, will self-seed with little or no encouragement. Did I mention one of my favorites, Verbena bonariensis? Poor baby doesn’t seem to have a common name (shall we call it Bonny Verbena?) Anyway, put some in the ground or a container one year, and you’ll have plenty the next. They’re tall with lacy leaves and smallish purple flowerheads. I actually like them in the middles of containers and beds, because you can see through them to what’ s behind, and they make a nice frame. I also have petunias growing through the bricks on my back walkway; I can’t quite bear to pull them up, even though they may be loosening the bricks, because they’re so pretty (and doing better than the petunias I bought to put in containers).
Seed Storage: Some seeds want to go straight into the ground, but most will remain viable for 2-15 years if stored properly. Seed companies package for the planting year, and seeds do lose some ability to germinate over time, but if you store them well, most of your seeds should be good to go in the spring.
The variables for good storage are moisture and temperature. Unless you’re storing seeds that retain a lot of moisture – mostly acorns and nuts – you should dry your seeds before you store them. Just put them on a cookie sheet and leave them out for a few days (labeled of course and out of the wind). If you can put them in a sunny window, that’d be good. No heat on yet in your house I hope!
Once they’re dried, the best containers for storing seeds are tin, aluminum, and glass. Next best are tin foil or laminated bags (you can buy these online). Worst are paper and cloth, because they let in too much moisture. So forget all those envelopes and head for the jars and tins. (Wash them first, of course, and dry well.)
You want to aim for the coolest temperature you can get easily. My plant propagation class taught that seed storage life is doubled for each 9⁰ decrease in storage temperature from 112-32⁰ F. For those of you in warmer climates this may pose some challenges; try cellars or garages. I just store mine in the garage, where it doesn’t really freeze. (Last year I put a container with a gorgeous sumac in the garage, watered it maybe twice, parked it near the window, and it’s performed beautifully this year.)
You can also propagate plants from cuttings. Fall is a good time to take cuttings of woody plants. If you have a friend or neighbor with a shrub you like, see if you can snip a stem and grow one of your own. If you live where there’s a long growing season, you can probably take softwood cuttings now too. Softwood refers to new growth on woody plants, like the green stems of a hydrangea. You can also take cuttings from perennials and annuals.
You’ll want to put your cuttings in clean potting soil, so have a rooting medium ready – vermiculite or some other sterile potting soil – and get some rooting hormone. You can get it at the garden center or even a hardware store: look for IBA in the ingredients. You’ll need sharp scissors and probably a razor blade.
For a softwood or perennial or annual cutting, choose a stem from a vigorous plant. Lateral stems make better cuttings than terminal ones, and you want to make the cutting in the morning before the plant has lost too much water. You need to use a razor blade to make a clean cut below a node. Nodes are the points on the stem where a leaf attaches; it’s at the node that the plant makes new roots. Remove the leaves from two or three nodes, where the new roots will form.
Snip any remaining leaves in half: the plant needs them to photosynthesize, but plants lose a lot of water through the leaves, so to prevent drying, trim the leaves.
Stick the cutting in the rooting hormone, count five, and then put it in the planting medium. Plant it down far enough that the leaves sit at the top of the soil to anchor the cutting and provide contact for the new roots.
If you’re taking a hardwood cutting, from a plant that has already lost its leaves, the process is similar. You may want to wound the stem by taking a slice out of the wood; this stimulates the production of roots. Dip this in the rooting hormone and pot it up. Water the soil, let it drain, water again, drain again, and then, to keep the cuttings from drying out, it’s a good idea to enclose them in some kind of plastic container, whether it’s a cover made by cutting the top off a large plastic soda (pop) bottle and inverting it over the plant, or a plastic bag tied at the top. Don’t put them in direct sunlight, but let them have some strong indirect light. Water again when the soil feels dry.
Different plant species have different specifics for cuttings, so if you know what kind of plant it is, an internet search for ‘propagate x plant’ will help you succeed. There are lots of really useful sites online with pictures to help you figure out what and where to cut.
Hope your garden is thriving.
