To Till or Not to Till

I grew up in Iowa, and I remember the 1980's drought in little mental movie clips.  I remember a newscaster on TV standing on very badly cracked soil, talking about all the farmers who could lose their crops.  I remember my grandparents watching heat lightning in the distance and being terribly upset that there was no rain to accompany it.  I also remember driving down the interstate and watching waves of soil blowing off the fields in the wind, because the plowed fields were just too dry to hold the soil down.  The solution to this last problem - according to the state - was for farmers to switch to no-till farming. 

This winter, while working on the Great Cardboard Project, I saw a similar thing happening in my garden.  It reminded me that it's always bugged me that gardeners are encouraged to till their soil, the exact thing farmers are not supposed to do.

What are the advantages of tilling?

1. weed control - conventional no-till farmers often use herbicides to clear the weeds from their fields before planting, which home gardeners (and organic producers!) are often loath to do
2. insect control - many insects live at least one stage of their life cycles underground, and can be disrupted by tilling during that period
3. warms the soil - tilling brings darker soil up from below and displaces organic material from the soil surface, allowing the soil to absorb more energy from the sun
4. dries the soil - tilling helps dry the soil in spring more quickly
5. incorporates organic matter into the soil

For all those advantages, though, my brother-in-law says his yields are higher with no-till methods.

What are the disadvantages of tilling?

1. organic material is consumed more quickly
2. more topsoil is lost to wind and rain
3. beneficial soil organisms are disrupted/destroyed
4. takes a lot of time and energy 
5. raises buried weed seeds to the soil surface
6. nitrogen in the soil is temporarily tied up

This year I have been turning the soil less and less, focusing more and more on mulching and hand-weeding and reminding myself that if I consistently keep the soil covered with organic material, the soil organisms will move that material down into the soil.  This is the sort of time-intensive manual labor that the plow and tiller were invented to replace, and I have yet to conceive of a good way to scale it up to larger areas.

As I've mentioned in other posts, I'm also trying to keep the beds planted as much as possible, and I'm working on a comprehensive planting/harvesting plan for next year to make that happen.  Keeping the soil covered with mulch and/or crops goes a long way towards suppressing weeds.

A few remaining summer crops, surrounded by bare soil being colonized by weeds

Seed-Starting Containers

Every year I have the same debate: what containers should I use to grow my transplants in.  Here's what I've tried:

1. butter/yogurt/ricotta containers
2. newspaper pots
3. clear Soho cups
4. nursery pots

Plastic food containers worked okay, but they're round, so they're not very space-efficient under the shop lights.  Also, it was very difficult to remove the root balls intact because the containers were so rigid.

Newspaper pots were a mess - I didn't like them at all.  (See No More Newspaper Pots for my list of reasons.)

Clear Soho cups worked pretty well, actually.  I didn't really like having the roots exposed to sunlight when I set them outside, so maybe I should have taped some paper around the outsides.  They're also round, though narrow so it was less of a problem.

Nursery pots are pretty good: they use space efficiently and hold a good amount of soil, and flex just enough for easy root ball removal without being floppy. They're also kind of boring and difficult to purchase. (Though easy to acquire for free at the wrong time of year.) I have some of these, though not as many as I used to because I threw a bunch out in a cleaning fit back in fall of 2010.


I've already used most of my meager supply of nursery pots, and will be moving on to Soho cups soon, if something more brilliant doesn't come to me.

Milk cartons?  Do schools still use milk cartons?  Anyone ever tried it?


PS - If anyone was wondering how the microwave lunch steamer trays worked out last year, they didn't.  They just weren't deep enough for the plants to grow much of a root system and I ended up tearing a lot of roots during transplanting that had grown down into the water dish below.

Establishing New Garden Beds

ETA: Sorry, this was somehow mistakenly published in the Jan 2011 posts!

Establishing a new garden is hard work, and I seem to convince myself to do it in at least one spot every year.  Here's what I've learned so far.


Gardening books often suggest double-digging to establish new garden beds, but I have found this to be a terrible idea around here.  The topsoil here is really only about 6-9 inches deep, with the subsoil consisting of extremely fine clay with large rocks buried in it.  Theoretically, when you double-dig you lift the top foot of soil up, loosen the underlying layer of soil with a large garden fork, and then put the top layer of soil back in place, adding soil amendments and air in the process.  The trouble is, if you try to do that in a location with less than a foot of topsoil, you end up mixing subsoil into your topsoil: in my case large, rock-like clumps of clay.  Also, after the first good rain the soil surface settles down into a cement-like, impermeable layer that just can't be good for plants.  There is a spot in our front flower bed where I double-dug my very first garden, mixing in compost and bagged garden soil; I only grew vegetables in this spot for one year, but four years later the soil in that section is still noticeably poorer (and lower, from me subsequently picking out those clay rocks) than in the rest of the bed. 

I also tried the lasagna garden method with the big backyard garden bed I added in 2010 (see Not Breaking Ground on the New Garden), laying down cardboard and covering it with 6-8 inches of compost I got from the city.  This worked extremely well for keeping the weeds down, but the soil and compost layers were still not well-mixed a year later when I dug a soil sample.  Proponents of the lasagna method claim that worms will slowly incorporate the new materials into the soil beneath.  I did find evidence of lots of worm activity below the cardboard (see Happy Pooping Wormies), but none above during that entire first year.  Maybe I messed it up by using finished compost instead of things like grass clippings and shredded leaves, but I was sufficiently discouraged by the results that I decided to just go back to single-digging.  Also, lasagna gardening is supposed to be less physically demanding than methods that require digging into the soil, but by the time I moved and spread and leveled all that compost I really didn't find this claim to be true, either.

My current preferred method for establishing a new garden bed is to add bagged soil, fertilizer, and vermiculite to the top of the bed, then mix it into the top layer of soil with a shovel, and level it and break up any clumps with a metal rake.  Then, before I plant it, I try to firm it down a bit.  Most books I've ever read say you shouldn't walk on the soil or press on it at all, but I do it anyway because I think it helps prevent that cement I was talking about earlier.  (When the soil is too loose the top layer gets dried out much faster, then the clay particles get stuck together, making the surface very impermeable and difficult to re-wet.  That's my theory, anyway.)  Last spring I also used garden sulfur in my community garden plot beds, which many sources suggest helps break up clay soils, though I can't tell if it did any good or not. I'll probably use it again.

Hmmm, I wonder what I'll think of this method in a couple years?

Don't Buy Seedlings at Grocery Stores

....unless you know what you're doing.















Why shouldn't you buy seedlings at grocery stores? Because these stores are just trying to make a buck, without regard to your gardening success. They know that if you take these plants home and put them in the ground and they die, you'll probably blame yourself. (As you probably should, since you ignored my advice!) Here are some good reasons why I can make such damning statements with confidence:
1) Grocery stores are not properly equipped to care for seedlings.
2) They offer plants at totally inappropriate planting times. For example, in the picture above they've got kale (which should have been planted weeks ago), yellow squash (it's about right for that now) and bell peppers (not for two more weeks by my calendar). Planting at the wrong time makes almost every top 10 list of gardening mistakes!
3) They offer things as seedlings that should be planted from seed in the garden. For most plants each transplant means a setback; the roots are traumatized by the exposure to light and dry air, and the plant has to re-grow some of the finest root-lets. Some plants, like those squash up there, grow so easily and so quickly from seeds that it just isn't worth putting them through a transplant.
4) Do you know where those seedlings grew up? Last year the east coast of the United States experienced unusually damp, cool weather throughout spring and summer. This, in combination with the transport of seedlings from southern states (where they are cheaper to grow because of warmer weather) for sale at northern stores led to a widespread outbreak of late blight, a devastating fungal disease that not only kills the tomato plant you buy at the grocery store, it kills every tomato plant you have, plus any potatoes you planted. And your neighbor's plants. And his neighbor's, and his neighbor's, and so on for up to 40 miles! Those seedlings that look so healthy at the grocery store may be harboring a deadly pathogen.

How about Home Depot or other stores like it? Pretty similar story. If you are a new gardener, and you want to buy plants rather than starting from seeds, go to a nursery or an experienced amateur grower. Not that they might not have a display like the one above, but if you ask them they'll probably tell you what not to buy.