Potting mix considerations

I have been doing a lot of thinking and reading about potting mix recently. For one thing, it is only four months till we start seedlings for 2016! (And only a month or so before we winter plant seed for perennials.) For another thing, I am thinking about using lots of wicking planters for greens in the upcoming year to improve their survival in our dry climate. Finally, a movable greenhouse has many benefits. I have been considering making our hoop house on the Littleton farm moveable. That way, we could start hardy spring greens, and then, once they were going and the weather was a bit more moderate, I could slide it away and start summer seedlings on the new site. Right now, spring plants languish in the increasing heat in the house, while delaying the summer tomatoes and peppers, and the tomatoes keep out the Fall kale and lettuce. However, a movable greenhouse is a big investment, and it might be better to just plant everything in containers, and then move and swap those. An unproven idea that we might try.

Anyway, there are lots of reasons for me to be considering potting mix strategies right now. For the past ten years or so, I have been using compost/ peat/ perlite type potting mixes. They are a logical extension to my organic gardening philosophy of feeding the soil, not the plant. However, I just now did some research and found a forum thread where a member was advocating a bark/ peat/ perlite mix, with the ratios being 5 1 1, very light and airy. They then add some commercial slow release inorganic fertilizer. The reasoning behind this is that a pot of fine grained potting mix contains a perched water table, where the natural attraction of the water to the soil particles is greater then gravitational pull. This zone becomes airless and is off limits to roots. So, some advocate separating the two functions of potting mix; structural support, and the provisions of nutrients.  Of course, this is just what conventional farmers do; they view the soil as an inert medium for holding plant roots, and then douse the soil with chemical fertilizer. However, since the pot is already an artificial growing area with different conditions then the soil, it makes sense that a different approach might be warranted. As an organic gardener, I would use organic slow release fertilizer, or a liquid fish/ kelp product if I switch over to a coarse grained medium.

I may do some experiments to compare the two approaches.

I also may include a small pot or bag of worm castings in larger, long term pots, which would provide fertilization without gumming up the whole pot.

Here is a link to the forum thread that got me interested in this: http://forums2.gardenweb.com/discussions/2842847/container-soils-water-movement-and-retention-xxii?n=329

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Summer of 2015 in review

I ran out of time to do weekly postings, so here is a summary of our season on the Littleton farm site. Overall, it was a great year! All of our trees survived and are growing well. The tomatoes yielded so abundantly that we sold them at Church, after the members and the Carmelites had taken all they wanted. Our favourite tomato varieties were taxi, moonglow, green zebra, black krim, black cherry, Ananas Noire, Siberian, and Cosmonaut Volkov. We also donated some to Christ in the City and The Divine Mercy Supportive care. We also harvested lots of squash, zucchini, and turnips, but it turns out that the members don’t really like turnips, so we will be planting less of them next year. As usual, the Costata Romanesco zucchini did really well at the beginning of the year, and the powdery mildew resistant PM straight-neck summer squash from High Mowing Seeds got off to a slow start but is still going strong. Our Mammoth Sunflowers topped 8 feet, despite a few wind storms, and we harvested at least some seeds ahead of the chickadees. We got at least one ripe cantaloupe, about the size of a soft ball. Next year we will try again to be truly successful growing melons in Denver. And we harvested cucumbers, beets, tomatillos, peppers, eggplant, lettuce, and lots of arugula. We tried growing beans up our sunflowers, but this was a failure. In fact, all the beans we planted gave a lack luster performance.

Due to the work of harvesting, we did not have time for infrastructure projects or planting Fall crops. In any case, due to the extremely dry weather in Denver during the Fall, late crops are hard to start.

We have lots of plans for next year. We will be rebuilding our fence to be more animal proof by attaching fine mesh wire along the base and laid out along the ground. Our greenhouse will be mounted on skids sliding on rails, so that we can start winter crops outside while the summer ones are still growing, and then slide the house over them latter. To help lettuce weather the dry climate, we will build wicking beds and shade structures, and to help the workers survive the heat, we will build arbors and plant some grape and hardy kiwi vines. We will be planting more trees, raspberries, hazelnuts, and currents, among other perennials. We hope to have more flowers and insect attracting plants.  We want to experiment with some sunken hugelkulture beds to see if we can get by without watering some crops at all. Our compost system needs to be improved put on track this Fall. We hope to plant cover crops of winter wheat and rye on some of the beds, and deep mulch others.

In a few weeks we will have a planning meeting to get things on track for next year, redefine our mission statement and project list, and reorganize our vegetable share plan. I will post more information as we go.

The fourth week of March/ the first week of April

Due to bad weather, we did not get as much done these weeks as usual.
In Littleton, we got the vegetable garden tilled, to create a better seed bed than was left by the tractor, and we got the fencing around the vegetable garden mostly set up. We planted rhubarb, lemon balm, and peppermint in our herb garden

We planted several hundred beet mix seedlings started in Littleton in the tilled beds in Lakewood. We also mulched some paths and cleared vines, weeds, and sticks from some of the fence lines in Lakewood.

In Littleton, we planted our fruit trees ( 1 meteor cherry, 1 montmorency cherry, 1 honeycrisp apple, 1 Red McIntosh apple, 1 golden delicious apple, 1 sweet 16 apple, 1 summercrisp pear, 1 Lucious pear, 1 Reliance peach, and 2 Italian plums, mostly on semi-dwarf root stocks.) We also spread lots of leaves and pine needles in the vegetable garden as mulch, and planted sugar snap peas, both from seed and as transplants, and Sugar pod 2 snow peas from seed.

The third week of March

In Littleton this week we rented a trencher and installed a water line and frost proof hydrant. We were donated a bunch of plastic storage units for our tools and supplies. Somebody also donated a picnic table and benches.

We planted flats of Sugar Daddy snap peas, Purple top white globe turnip, Yellow Granex onion, and radishes in the Littleton greenhouse under row cover, using our standard potting mix. We planted some small news paper pots of Sugar snap peas. (The greenhouse is unheated: however, at this time of year the double coverage should keep things from freezing.) We planted about 250 sweet peppers (Marconi Red, Jimmy Nardello, Ampuis, California wonder red, California wonder orange, and a few others) and 100 eggplant (Early black and Black Beauty) in plastic six pack with our standard mix. The peppers and eggplant are now in a heated frame at my house.

We started to pin down landscape fabric in our work area, which will eventually be covered by mulch or gravel.

In Lakewood, we decided that the old compost/ mulch area was unsightly and not very functional. We started the process of tearing down the old bins and forking out the compost materials. (Things did not decompose very well; they seem to have dried out.) We will be building new bins in the shade of the greenhouse, screened from view by a grape and kiwi arbor. We forked over 300 square feet of the beds that we rototilled last year to remove the grass, and re-mulched the paths. We also started gathering and piling all the rocks and concrete chunks on site to build a raised rock flower bed.

The second week of March

 Two weeks ago, we finished building an Eliot Coleman style high tunnel/ greenhouse, with two automatic vent openers. The frame was built of 20′ rebar rods sheathed in PVC pipe, with the ends buried in the ground.
We got a lot done this week.
In Lakewood, we planted seed lettuce, lentils, and peas in the greenhouse under row cover. The lettuces were various heat tolerant types. By planting them in the greenhouse, we will be able to select for the most heat tolerant plants to save seed from. Before we planted, we hauled all the old mulch and compost out of the greenhouse, since it might be harbouring slugs, and spread it around the trees. We also repaired the bridge over the irrigation ditch.

In Littleton, we planted Early Flat Dutch and Copenhagen Market cabbage, Waltham 29 broccoli, and a beet mix in flats in the greenhouse, under row cover. We used our standard potting mix, a blend of peat, compost, and perlite amended with lime, bone meal, azomite, and organic fertilizer.

We also cut up bushes to make a truck access, spaded the other half of the greenhouse beds, rebuilt the greenhouse doorway, and dug a ramp so that we can roll wheel barrows into the greenhouse.

A farmer kindly brought his tractor and chisel plow in to break up the vegetable garden area. So we now have 10,000 square feet of broken ground. (About a quarter of the whole field.) Since the weather is dry and hot, all the grass should be dead in a day or so. We will have to get to work quickly to take advantage of the open ground before weeds do. Part of the garden will probably be mulched in preparation for planting, part will be sown with a cover crop before tomatoes and squash are planted at the end of May, and some beds will be worked into a fine seedbed without mulch for planting cool weather, small seeded crops like lettuce.

New Littleton Site! Helping to feed the Carmelites!

The Saint Isidore Society has been allowed to use a new site; an acre field located near Gallup Street and Littleton Boulevard in Littleton CO. We will be growing enough produce for the nearby Carmelite convent, as well as for the participating members. We hope to eventually plant fruit trees and bushes, as well as a large vegetable garden.

Our site in Lakewood will be moving into its second year this spring. We will be continuing  our operations there as well as developing our new site in Littleton.

We have already erected the frame of a greenhouse on the new site, which should be ready for use in a week or so. It will be very much like our Lakewood greenhouse featured in earlier posts here: an Eliot Coleman style hoop house with a plastic cover.

If you want to participate, contact us and we will send you the exact location of the site.