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How to propagate plants

  • Marie Narlock
  • Propagation sounds like something you do in a white coat, but in reality it just means you're making new plants from old plants. That time you bought a packet of seeds and planted them? You were a propagator. Congratulations.

    But here's a horticultural news flash: Sometimes you don't propagate plants from seeds.

    Strange, right? Sometimes plants are propagated by cuttings and other methods. You can learn about these methods — and gain hands-on practice — at the Master Gardeners' upcoming propagation class on March 9 at the Falkirk Cultural Center in San Rafael. You'll go home with your very own baby plants.

    "I love showing people how easy it is," says propagation teacher Jessica Wasserman. "People are always blown away how simple propagating is — and how much they'd have to pay at the nursery for a similar plant!"

    True, propagation is great for frugal gardeners like me who often scoff at nursery price tags. And it's sustainable because you don't have to jump in your car every time you have a hankering for a new plant (that comes in a petroleum-derived plastic pot). You can be sure that plants you propagate are free of pests and pesticides, and you can even grow hard-to-find plants, since there are an unbelievable variety of seeds that can be purchased.

    Chances are you have pretty much everything you need to be a successful propagator in your garden already. Here is a quick rundown of the propagation methods:

    Sowing seeds

    Let's start with the layup. Everyone knows how to plant seeds, right? Well, almost right. It turns out some of us are a little rusty. Here are a few things worth remembering.

    If you're starting seeds indoors, use sterile soil. Yes, you can sterilize soil yourself in your oven, but would you, seriously? Instead, save yourself the chance of dumping a pan of dirt in your oven and buy yourself a bag of sterile seed-starting mix. If you're planting outdoors, just be sure the soil is loose and uniform in texture.

    Next, be sure to only cover seeds to about the depth of the width of the seed. This means that tiny seeds barely get any cover. In fact, some seeds prefer to be left uncovered. Why? Because seeds need light and warmth to germinate. That's why they also need plenty of sun (outdoors or near a window) for germination.

    Watering is a little trickier. Seeds are like the baby bear: they don't want too much or too little water. They want it just right. Aim to keep the soil moist but not saturated. And avoid planting seeds outdoors in cold, damp weather, since this could be a recipe for failure.

    Succulents and 'pups'

    Succulents — those colorful, fleshy, unthirsty plants — are about the easiest plants of all to propagate. Even easier than seeds. Honestly, I know someone who cut large chunks off a friend's plant, tossed them into a trash bag where they stayed for months, and then planted them successfully. But we're — ahem — master gardeners, though, so we cannot officially recommend this technique! Instead, here are the basics of propagating succulents.

    With succulents, you can often see the baby plant growing right on the mama plant. All you do is snap off these "pups" and pop them into some soil and you're done. OK, so there's a wee bit more to learn. But not much. You may have a greater success if you wait a day or two (sans trash bag) before planting. You'll get your pick of sedums or Crassula tetragona, commonly known as miniature pine trees, at the March 9 class.

    Nip and plant

    Ever wondered why there are varieties of fig trees that have been around for 25,000 years? Or why there are ancient grape and olive cultivars?

    It's not because someone kept seeds in a refrigerator. It's because these plants can be rooted using hardwood cuttings. How does this work?

    You snip off a 6 inch to 12 inch stem that has "nodes" on it (the places where new growth will form) and plant it in the ground just above the top bud. These cuttings generate roots and can be transplanted after a year or so of growth.