Q. I just read a list of the 10 'dirtiest foods' in America—the ones most associated with outbreaks of food poisoning, like cantaloupes, scallions, packaged lettuce, and peaches. I have also seen a 'dirty dozen list' of produce with the most pesticide residues. I can't afford to buy everything organic on my modest income, but I would like to limit my exposure to the worst offenders, and I do have a garden. So I'd like to put some fruits and vegetables that are either the 'dirtiest' or most chemically contaminated at the top of my planting list. But I need to balance this wish with ease of growth and my odds of success. So—which do you consider to be worth the effort to grow yourself?
- ----Cathy in Glenside, PA
The numerical rankings change a bit from year to year, but it's mostly the same dozen fruits and vegetables every season. How badly contaminated are the twelve? The EWG estimates that you can reduce your pesticide exposure an astounding 80% by avoiding those items or buying them organically grown. (Or, in this case, by growing them yourself.) We'll use the EWG's most recent list (dated 2011, compiled from tests of the 2010 harvest) to answer Cathy's question about ease of home growing.
#1: Apples. Difficult and time consuming. They need a lot of room, several years to reach fruiting maturity, and a lot of care and attention. (See this PREVIOUS QUESTION OF THE WEEK FOR SOME OF THE DETAILS) The trees must be pruned every winter and the fruits must be thinned every Spring. And they require a regular schedule of organic sprays to control pests and disease. But mature trees produce enormous yields, and they're much easier than peaches.
#2: Celery. Close to impossible for most home gardeners. This finicky crop requires massive amounts of food and water and temperatures that stay between 55 and 75 for three or four months. So either buy organic celery or try growing one of the 'celery substitutes' from the same plant genus (Apium), like celeriac (Apium graveolens rapaceum), a huge root that grows celery-like stalks, or cutting celery (Apium secalinum), which looks a bit like parsley and is also known as leaf celery, soup celery and smallage.
#3: Strawberries. Pretty close to easy peasy; your main job will be to protect the fruits from squirrels, slugs, squirrels, birds and squirrels. Plant several different types (early and late season June bearers and a patch of day-neutral berries, which are smaller but have a much longer season) and you can enjoy fresh berries pretty much all summer—and your home grown ones will taste much better than any berries you can buy.
#4: Peaches. Incredibly difficult and time consuming. Peach trees require a lot of room and take three or four years to start bearing fruit. They must be pruned every winter and the fruits must be thinned heavily every season. (See this PREVIOUS QUESTION OF THE WEEK FOR SOME OF THE GORY DETAILS.) The remaining ones will then be attacked by numerous pests and some of the most depressing diseases in agriculture, especially the notorious brown rot. The upside? If you're willing to devote a lot of time to their care, there are organic sprays that do as good a job as chemicals at defending the fruits; and mature trees can produce ridiculous amounts of peaches, which can be preserved for year-round use.
#5: Spinach. Very easy to grow in the cooler weather of Spring and Fall. Spinach can't take summer heat, but you can keep it alive and producing throughout the winter in much of the country by using floating row covers or plastic covered hoop tunnels.
#6: Nectarines. Similar to peaches, but their tougher skin makes them a little easier to grow.
#7: Grapes. Grape vines need room, full sun, magnificent airflow and several years to begin bearing fruit. After that, you can largely avoid their biggest problem—disease—by heavily thinning the leaves and fruit clusters throughout the season. And you can make your own raisins if the harvest is huge.
#8: Sweet bell peppers. Very easy to grow; they just require a long season to achieve their final ripe color of red, yellow or orange. (Green peppers are immature and contain little to no nutrition.) Grow smaller-fruited varieties; they mature much faster, and you'll pick ripe fruits a month earlier. If you overwinter the plants indoors, you can get big ripe bells by the Fourth of July in subsequent seasons from these bigger, older plants. (SEE THIS PREVIOUS QUESTION OF THE WEEK FOR DETAILS ON OVERWINTERING.)
#9: Potatoes. Maybe the easiest on the list; just be sure to protect the tubers from light. You can even grow them above ground in big compost bin-like towers and harvest a good amount from a relatively small area. Grow some for fresh eating and some for long-term storage.
#10: Blueberries. Not at all prone to pest or disease problems. All these shrubs need is a lot of sun, an extremely rich and acidic soil, and protection from birds, who will fight you for every tasty berry. If you have a dedicated area where the soil can be kept highly acidic and the shrubs have room to grow tall and spread wide, you'll pick gallons after a few years. Grow different varieties—early-bearing, mid-season and late—and you can really stretch the harvest. And blueberries freeze well for winter eating. SEE THIS PREVIOUS QUESTION OF THE WEEK FOR LOTS OF DETAILS.
#11: Lettuce. Just as easy as spinach—and just as heat-intolerant.
#12: kale. As easy as spinach and lettuce, but much more cold-hardy. A very reliable winter green.