Tag Archives: gardening

cold stratification

Mid-February, time for a gardening post. It’s kind of like when you start following your favorite sports team before the season starts, and you are excited because anything is still possible. I am especially excited though because I have a new house, it has a garden, and it is really the first time I have ever had a garden. I’m going to grow some annuals, mostly in pots, but what I really want to focus on is perennials. I’m picking mostly perennials, mostly natives, and mostly plants that are edible in a pinch, although garden for food is not my top objective (my top objective is butterflies and other pollinators, followed by interesting appearance including flowers, followed by food potential). Which brings me to cold stratification. I have started a bunch of seeds in the basement under lights over the last two weeks, but so far nothing has happened. These perennial seeds seem to be tougher than the annuals I have been used to in the past. One reason is some of them apparently need cold stratification.

Where I live the snow is rapidly melting, leaving behind a landscape that seems almost barren and asleep. However, for many native plants and quite a few garden perennials, it is this act of freezing and thawing that awakens them and actually increases their ability to survive and reproduce. Cold stratification is the term used to describe this very basic need; the need for winter.  Winter has the ability to soften the outer seed coat of some of nature’s toughest seeds through the action of freezing and thawing in a moist environment. For many plants that require stratification, this process can take up to 2 months and typically occurs between 34 and 41 degrees Fahrenheit. During that time, the seed coat softens and embryonic growth is stimulated. Eventually, the embryo bursts through the softened coat and begins the process of germination.

For those of us who enjoy starting our own flowers, there are some classic perennials that require a period of cold stratification to increase germination. One example is Echinacea, a personal favorite of mine. Echinacea is a plant gifted with many benefits. Most home herbalists are aware of its medicinal properties and gardeners love it for its beauty, low maintenance requirements and as a mid to late season nectar source for beneficial insects. For these reasons, Echinacea has a place in nearly every garden and farm.  But purchasing mature Echinacea plants from a nursery can be expensive and often some of the most interesting varieties (Rare or endangered native prairie Echinacea varieties have only been available in seed form recently.) are not available commercially. For these reasons, I started growing my own Echinacea from seed a number of years ago. In the beginning, I had mixed success. Without a period of cold stratification, the germination rate for this garden beauty can plummet to less than 30 percent. However, with stratification, it is possible to germinate nearly 100 percent of all Echinacea seeds that are started.

So I’m going to try throwing some seeds in pots in the backyard, even though it is freezing. But 30% doesn’t sound that bad to me. With a packet of 100+ seeds costing $2-4, I can afford to plant 3 seeds for every one that comes up. Still, I’m waiting a bit nervously for that first one…

a dream of spring, or plant geeks, seeds and where to find them

I’m enjoying this book by Eric Toensmeier, part of the new (at least to me) generation of American permaculture enthusiasts.

I might not enjoy it as much if I hadn’t already read Edible Forest Gardens, but this book is in part a narrative of how that book came about. These are the kinds of things gardeners read in January (at least, until George R.R. Martin gets around to publishing A Dream of Spring…)

I like this paragraph about being inspired by native peoples’ management of wild landscapes:

As a budding ecologist in the 1970s and 1980s, I learned that the best we can possibly do as environmentalists is to minimize our impact on nature. The ideal footprint would be no footprint at all. That doesn’t really give us a lot of room to breathe, and with that as a model, it’s easy to see why the environmental movement has not won wider acceptance. The most profound thing I have learned from indigenous land management traditions is that human impact can be positive – even necessary – for the environment. Indeed it seems to me that the goal of an environmental community should not be to reduce our impact on the landscape but to maximize our impact and make it a positive one, or at the very least to optimize our effect on the landscape and acknowledge that we can have a positive role to play.

Urban forestry is a good place to start with this vision, and there is some energy behind that (although also a fair amount of negativity and cynicism opposing it). Once we get the trees we want, we can decide that it is okay for a city to have a shrub layer and an herbaceous layer too, and we can work on those. There is also a fair amount of energy and funding behind water management in cities. Once we have the soil and the plants, it seems fairly obvious to bring the water to them. Again there is some cynicism and negativity out there, and a divide between energetic but sometimes scientifically challenged hippies, and the oh-so-practical but oh-so-cynical engineers, who actually could make all this work if they put their minds to it.

One last thing on this book – it has an appendix which lists some sources of seeds and plants I wasn’t familiar with. This is an area where Google lets us down, because these companies sell all sorts of interesting things that I have been looking for, and the typical search algorithms have not been getting me there.

  • Oikos Tree Crops – focuses on native nut and fruit trees, also has some hard-to-find perennials like several varieties of Sunchoke tubers
  • Kitazawa Seed Company – focuses on seeds of Asian vegetables – lots of Thai chilies, basils and eggplant varieties here! I’m also interested in “Malabar Spinach”, which sounds like it could provide me salads all summer with minimal effort, as long as I eat it fast enough so it doesn’t eat my house. (I’m also interested in hardy Kiwis and hops, but these woody vines are a little scarier because if you let them go, you might need a chain saw to remove them.)
  • Evergreen Seeds – another source of Asian vegetable seeds
  • Edible Landscaping – these guys will ship some hard-to-find fruit tree species, like Asian persimmons and pears
  • Fedco Seeds – all kinds of vegetables and fruits, seeds and plants
  • Food Forest Farm – Toensmeier’s site, with a limited selection of very interesting plants
  • Fungi Perfecti – what it sounds like, mushrooms
  • High Mowing Organic Seeds – another general purpose seed company
  • Logee’s – obscure tropical plants, looks great for the houseplant and patio gardener, not so focused on edibles
  • One Green World – lots of fruits, nuts, and berries, focus on the Pacific Northwest
  • Raintree Nursery – more fruit and nut trees
  • Richters – lots of vegetable and herb seeds

birds, bees, bugs, plants

On the green infrastructure front, there are lots of resources out there on what plants support what kinds of wildlife.

“Bugs” have a PR problem as a group, but they have their charismatic members – bees, butterflies, and dragonflies to name a few. If you support these, you will probably support others by accident. There is plenty of information out there, for example:

The Xerces Society for Invertebrate Conservation has a ton of free publications on plants, pollinators, and design; including bee-friendly plant lists for all regions of the United States and several other countries.

The Lady Bird Johnson Wildflower Center has a ton of free native plant information, including recommended mixes to attract various types of wildlife in all U.S. states and Canadian provinces.

Finally, the Natural Resources Conservation Service (part of the U.S. Department of Agriculture) has free fact sheets on about a thousand plants.

A lot of good can be done for wildlife and humanity on small scraps of land, and even more good could be done if we gave serious thought to how all those scraps of land fit together and connect to larger parks and preserves. So let’s get out and plant something this spring, even if it’s small. Or if you have a scrap of land but you don’t feel like planting anything, find a frustrated armchair gardener who doesn’t have their own scrap and let them plant something on yours.

Subirdia

Welcome to Subirdia: Sharing Our Neighborhoods with Wrens, Robins, Woodpeckers, and Other Wildlife

NPR reviews an upcoming book called Subirdia, which says that in temperate areas, there are more bird species in the suburbs than in cities or even forests:

So what have suburbs got that forests don’t? Suburbs, he says, offer a wide range of artificially designed garden habitats, providing a smorgasbord of nuts, fruits, seeds, insects and ponds, in dense concentrations. Because they are rich with different kinds of bird food, suburbs are rich with different kinds of birds…

But let’s not get crazy about this: suburbs are not the birdiest zones on earth. Any patch of tropical forest, with its dazzling populations of plant and animal life, will trump a garden-rich suburb. But if you are comparing suburban bird diversity to temperate wild spaces — say the Cascades, the Smokies or the Adirondacks — the suburbs, shockingly, win.

So maybe our goal in denser cities should be to create a landscape with more of this variety of garden habitats. That is doable, and a much more attainable goal than trying to create forest-like habitat in cities. There are some shy species that won’t come to the city, but the city can be pleasant for a wide variety of species, even humans, if we work at it.