GWN Propagation Talk and Seed Exchange

Last Thursday, Country Mouse and I had the great pleasure of attending a propagation talk and cuttings exchange. The event was organized by the Gardening with Natives group of the Santa Clara Valley chapter of the California Native Plant Society.

Speaker was Pete of East Bay Wilds, an experienced propagator who owns a landscape design/install business and a small nursery. People could barely squeeze in. I was exciting and encouraging to see so much interest in gardening with natives.

We first went around the room to talk about what we had brought (about half the people had brought seeds or cuttings), and then the actual presentation began. Pete talked about propagation from cuttings, Iris division, and sowing annual seeds. And below are the tools of the trade he brought.

Propagation from cuttings. For cuttings from natives, Pete uses a mix he makes himself:

• 1/2 fine horticultural sand
• 1/4 (or a little more) potting soil
• Pumice and Lava rock

Pete likes this mix because it stays evenly moist and does not dry too quickly. Pete admitted he is not too particular about sterilizing the soil -- he leaves it out in the sun to dry it out after use. But for some plants that are susceptible to fungus , such as Arctostaphylos hooverii, he uses a fresh mix.

Pete then says to proceed as follows:

1. Sterilize the pots in a solution of 1:24 water:bleach
2. Dips pruners in alkohol.
3. Take a cutting, ideally right at the edge of green/brown for Arctostaphylos. 
4. Remove most leaves. If the top of the branch is floppy (he showed us a Toyon leave that did that), cut it off. For a branch with very large leaves, cut the leaves in half. You want for the energy to go into rooting, not into the leaves, but you must leave a few leaves.
5. Put the cutting in a nutrient solution for a minute or two. Pete likes Earth Juice.
6. Dip the cutting in rooting hormone. Pete use Rhizopon AA#3. Wear gloves when working with the hormone. It's not toxic to the environement, but humans don't need it in their bodies. 
7. Put the cutting into the pot with the soil mix, 1-2 inches deep. 
8. When planting, top-dress with decomposed granite. 

Pete then uses bottom heat on his cuttings and keeps them moist. He keeps his cuttings in the sun and mists them 2-3 times/day, but it's usually possible to get good results with part shade and misting once a day or every 2 days. And for things that root easily, such as Ribes or Heuchera, you're probably OK without bottom heat. Below, a cutting that demonstrates how Pete cuts leaves of large-leaved plants.

Native Iris. A flurry of questions brought us to the topic of Iris division. Here's what Pete says:

• Divide native iris in November (not in spring)
• Take out the whole plant and divide, then replant. Make sure you expose the roots and rhizomes to some light. 
• It's fine to add a little compost to the soil for Iris and other plants that live under a lot of duff (redwood habitat plants). Other natives, especially chaparral plants, don't like compost. 
• Fertilize with kelp spray on the leaves if you like for an extra healthy plant. 

Annuals. The final part of the talk was devoted to annuals. Pete told us he has two kinds of mulch in his own garden, bark and decomposed granite. He's found that Sierra Ginger and Blue Fines works well for growing annuals on, but Gold Fines does not.

He sows the annuals after the rains has started and rakes them in. He has not had a problem with birds eating the seed sown in decomposed granite. People asked him which plants might do well in bark mulch, and we jointly came up with a few:

• Chinese Houses 
• Gilia tricolor
• Globe gilia
• Poppies
• Clarkies

Other annuals do much better in decomposed granite.

We were sorry to see the presentation end, but also excited to start the actual exchange (or giveaway). The GWN group generously provides little seed packets, and the eager native gardeners walked around and picked up seeds and cuttings, asking questions of the seed owners and Pete. Below, some seeds that Pete had collected, and a buckeye that Diane brought -- the first from here baby tree.

I myself left with a Ribes sanguinium (native current) cutting and some Layia platyglossa (tidy tips) seeds. I'm hoping to create some small decomposed granite paths and sow wildflowers there, then cover the paths with bark mulch for summer and fall. The effect should be a river of wildflowers, beautiful in my mind's eye.