Not really a botanically-correct statement, but you know what I mean. John Porter’s previous blog post did a great job of explaining cucurbit reproduction (loved the Pucchini). Though I was surprised to learn “not getting any fruit” is actually a problem. Can’t say I’ve had an issue with that, ever. We have a really vibrant bee population and they’ve been super busy.
I love growing squash of all sorts, despite not being a terribly gifted vegetable garder. Past Garden Professors posts have addressed this issue. One might ask, why on earth would a two-person household need a 60-foot-long row of zucchini? Because we can! Though if I recall, I intended to go back and thin the row. Whoops.
The zucchini hedge. And those aren’t weeds, they’re *biodiversity*.
By late summer, we usually end up with gummy stem blight, powder mildew or squash stem borer No sign yet, though any of these goodies could show up next week. The plants are all healthy and ridiculously enormous. It’s been very warm and dry, but we have a nice drip irrigation system in place.
So guess what happened when we got too busy to check on them for three days? Many more were still on the plants when I snapped this pic. I’ve worked zucchini in some form into every meal except breakfast. Joel’s still being a good sport. Next step is anonymous *gift* bags to folks at the office. Though I think I’m getting a reputation.
Normal-sized zucchini at top of photo for reference. Aargh.
Not all zucchini taste alike, as true fans know. The pale hybrid Bossa Nova, right, has very creamy and tender flesh with seeds that are really only noticeable when it gets, er, hefty. Bossa Nova is a recent All-America Selection and perfect for use with those spiralizer thingies. The ribbed/striped variety is Costata Romensco – an heirloom variety with really wonderful flavor. Humongous plants though, probably not the best choice for square foot gardening fans. Tigress is the white-flecked green selection, allegedly more disease resistant than most. Bright and sunny Gold Rush, an old-school AAS selection, adds some color and is a bit sturdier/keeps longer than yellow summer squash.
I won’t be trying to save seeds – as John noted, can be very tricky/futile when there are other cucurbits about. Plus it’s too much fun to pick out next year’s selections from the winter seed catalogs, when the prospect of bountiful zucchini stacked like firewood actually sounds appealing.
One of the things I miss (and sometimes don’t miss) after my move from West Virginia to Nebraska is writing my weekly garden column for the Charleston Gazette-Mail newspaper. It was a great way to always keep thinking about new things to talk about and a great way to connect with the public.
After I left, the newspaper replaced me with a team of 4-5 local gardeners who would take turns writing about their different gardening insights and experiences. Some have been really good, like the ones who were my former Master Gardener volunteers. However, sometimes I find the bad information and attitude of one of the writers off-putting and even angering.
Take for example this missive which equates sustainable agriculture (a term which is pretty well defined as a balance of environmental stewardship, profit, and quality of life) solely to permaculture and biodiversity while espousing an elitist attitude about “no pesticides, no fossil fuels, no factory farms, growing all you need locally and enhancing the land’s fertility while you’re at it.” He got all this from an old photo of dirt poor farmers who were apparently practicing “permaculture” – which I’m sure was foremost on their minds while they were trying not to starve to death. The fact is that our food system (and the food that today’s low income families) depends on comes from a mix of small and large farms. And most of those “factory farms” are actually family owned, and not everyone can afford to grow their own food or pay the premium for organic food (which still has been treated with pesticides and is in no way better or healthier than those conventionally grown).
Now, I know I no longer have a dog in that fight, but when I see bad information, especially when it is aimed toward an audience that I care deeply about I just have to correct it. So two weeks ago when I saw his latest gem of an article berating a woman (and basically anyone) for using lumber (and those who work as big box store shills to promote them) to build raised bed gardens and should instead till up large portions of their yard for the garden I was aghast. Putting aside the horrible advice to till up the garden (which we’ll talk about in a minute) or the outdated recommendation of double digging (proven to have no benefit), that advice is just full of elitist assumptions toward both the gardener and toward the technique. It is especially ridiculous and ill-informed to suggest that tilling up a garden and destroying the soil structure is much better ecologically speaking that using a raised bed (and we’ll talk about why in a little bit).
Don’t want to do a raised bed? Fine, it isn’t for everyone. But that doesn’t mean you should go out and till up a large patch of land that will degrade the soil, lead to erosion and runoff, and reduce production. It does not do anything to improve drainage nor aeration.
So let’s do a breakdown of why I find this article, its assumptions, and bad science so distasteful:
Bad Assumptions (and you know what they say about assuming)
The gardener didn’t have a reason for a raised bed other than she had been told that’s the way you do it.
This assumption fails to take into account the many different reasons why a gardener may prefer to use a raised bed. Does she or a family member have mobility limitations where a raised bed would provide access to be able to garden? Or does she have space limitations for a large garden patch? Would a raised bed make it easier for her to manage and maintain the garden? Making a blanket pronouncement against the technique fails to use empathy to see if it actually would make gardening more accessible or successful for the gardener. Is she wanting a raised bed because the soil in the ground at her house is too poor or contaminated? West Virginia is notorious for having heavy clay, rocky soil that is pretty poor for growing most crops. It can take years of amending to get it even halfway acceptable for gardening. Or perhaps she lives on a lot that had some sort of soil contamination in the past and she’s using raised beds to avoid contact with the contaminated soil.
Raised beds also have some production advantages – the soil heats up faster in the spring, allowing for earlier planting. A well-built soil also allows for improved drainage in areas with heavy soil or excess moisture.
The gardener has access to equipment to till up a garden space, have the physical strength and endurance to hand dig it, or is she able to afford to pay someone to do it for her?
Raised beds can often be easier for gardeners to build and maintain, often not needing special equipment or heavy labor. If the gardener isn’t supposed to benefit from these efficiencies, how will she go about tilling up the soil for her new garden. Does she or a friend/neighbor have a rototiller or tractor she can use? Is she physically capable of the often back-breaking work of turning the soil by hand? Or does she have money to pay someone to do it for her? So these “cheaper and easier” methods he describes could actually end up costing more and being harder than building a raised bed.
The raised bed has to be built out of lumber, which apparently only comes from the Pacific Northwest and is a horrible thing to buy. First off, raised beds can be built out of a number of materials. The list usually starts with lumber. Some people tell you to use cedar (which does primarily come from the PNW), since it is more resistant to decay, but plain pine that’s treated with a protective oil or even pressure treated is fine (it used to be not OK back before the turn of the century when it was treated with arsenic, but most experts now say it is OK since it is treated with copper). The dig against the PNW lumber industry is as confusing as it is insulting, since there’s lots of lumber produced on the east coast, and even a thriving timber industry right in West Virginia. Most lumber these days is harvested from tree farms specifically planted for the purpose or by selective timbering that helps manage forest land for tree health and sustainability.
The list can go on to include landscaping stone, concrete blocks, found materials like tree branches, and on and on. These days, you can even buy simple kits you can put together without tools and with minimal effort that are made of high-grade plastic or composite lumber. They’re getting cheaper every year, and can be especially affordable if you find a good sale or coupon.
Heck, a raised bed doesn’t even require the use of a frame at all….just a mound of well amended soil in a bed shape will do. No need to disturb the soil underneath, just get some good topsoil/garden soil in bulk or bags from your favorite garden center, mix it with a little good compost, and layer at least 6 inches on top of the soil. Use a heavy mulch on top if you are afraid of weeds coming up through the new soil.
The soil she’d buy is trucked in from Canada.
I’m guessing this has some sort of assumption that the soil a gardener should be putting a raised bed is like a potting mix composed primarily of peat moss. While many gardeners are trying to decrease the use of peat moss, which is a non-renewable resource harvested from Canadian peat bogs, the recommended soil for a raised bed is not potting mix or one that even contains a large amount of organic material. The recommended composition of raised bed soil is largely good quality top soil, which is usually sourced locally, mixed with a bit of compost which could be from home compost, a local municipal composting facility or producer, or from a bagged commercial product that is likely from a company that diverts municipal, agricultural, and food wastes into their product.
Bad Advice based on Bad Science (or lack thereof)
Tilling or disturbing the soil is a common and acceptable way to prepare a garden.
More and more evidence is emerging that tilling or disturbing the soil is actually one of the worst things you can do in terms of both production and environmental impact in agricultural production. First, tilling disturbs and in some cases destroys the soil structure. Destroying the soil structure allows for increased erosion, especially when the bare soil is washed away during heavy rains or blown away in heavy winds. Excess tillage and wind is what actually led to the dust bowl, which actually led to the early promotion of conservation tillage practices through government programs like Conservation Districts (and also gave us some great literature, thanks to John Steinbeck). Aside from the soil particles that erode, having open, tilled soil leads to nutrient runoff that contribute to water pollution.
One other structure negative is the production of a hardpan or compressed layer of soil that occurs just below the tilled area. This results from the tines of a tiller or cultivator pressing down on the soil at the bottom of where it tills and can drastically reduce the permeation of water and gasses through the soil.
The aggregates in the structure of un-disturbed soil provide myriad benefits to soil health, especially in providing the capacity for the growth of good microorganisms. Studies have shown that the population of soil microbes is drastically higher in agricultural soils that haven’t been tilled. Therefore, tillage reduces soil biodiversity.
One of the reasons for increased soils microbes in no-till soil is an increase in soil organic matter. No-till allows for some crop (roots, etc) to remain in the ground and break down. Tillage also incorporates more air into the soil, which does the same thing that turning a compost pile does – it allows the decomposition microbes to work faster in breaking down organic matter. This increased activity then decreases the amount of organic matter. So tilling the soil actually reduces organic matter. The structure and organic matter also allows no-till soil to have a higher Cation Exchange Capacity, or ability to hold nutrients.
When the carbon in the organic matter in the soil is rapidly depleted after tillage, it doesn’t just disappear. The product of the respiration from all those bacteria and fungi is the same as it is for all living creatures – carbon dioxide. The organic matter held in the soil therefore provides a great service (we call this an ecosystem service) in that it sequesters carbon from the environment. This can help mitigate climate change and even effect global food security.
Double digging does a garden good.
Look through many-a garden book and it will tell you to start a garden bed by double digging, which is a term used to describe a back breaking procedure where you remove the top layer of soil, then disturb a layer beneath it and mix up the layers. While it may not be as drastic as running a tiller or tractor through the soil, it still destroys the structure with the same negative outcomes as above. Additionally, while many gardeners swear by it, there is evidence that the only benefit to come from it is to prove to yourself and others that you can do hard work. It has no benefit for the garden and usually negative effects on the soul, psyche, and back of the gardener.
Large tilled up gardens are easier to maintain. One of the benefits of gardening in a bed, raised or otherwise, is that the close spacing allows you to grow more stuff in a smaller area. By reducing the area under production, you also reduce the labor and the inputs (compost, fertilizer, etc) that are used. Using the old in-ground tilled up garden method where you grow in rows means that you have more open space to maintain and will be using inputs on a larger area that really won’t result in more production (it is really wasted space and inputs).
So, how do you start a garden if you don’t want to build a raised bed and know that you shouldn’t disturb the soil?
So you realize that tilling up the soil is really bad from both an ecological and production standpoint, but you don’t want to build a raised bed structure? That’s perfectly fine. Gardening in a bed, raised or not, is a great, low-impact gardening practice.
To get started, you don’t have to disturb the soil at all. Simply adding a thick layer of compost and topsoil on top of the soil in the general dimensions of the bed is a good way to start a bed. No need to till or disturb. And over time, the organic matter will eventually work its way down into the soil. If you have really heavy (clay) soil, you’ll probably want to start with a fairly deep (at least 6 to 8 inches) layer of soil/compost.
Just cover with your favorite mulch to keep it in place and reduce weeds (I prefer straw and shredded newspaper, but you can use woodchips as long as you don’t let them mix in with the soil – something I never can do in a vegetable garden where I’m planting and removing things on a regular basis). Keep in mind that a good width for a vegetable bed is about four feet and you want a walkway of at least two feet between them. This allows you to not walk on the good soil, which can cause compaction.
If the spot where you want to put your bed is weedy, use your favorite method to remove weeds before laying down the layer of compost/soil. This could be through herbicide usage (keeping in mind most have a waiting period to plant, though some are very short) or mulch. If you are planning ahead (say at least a year), our Garden Professors head horticulturalist suggests a layer of woodchip mulch 8-12 inches deep that can turn a lawn patch into a garden patch. They reduce the weeds and build the soil as the break down.
It’s been awhile since I wrote about, or recommended a blog I like which I often use as a source of something to share to The Garden Professors Facebook Page, so I thought I’d revisit the topic this month.
Add a friend, chef Michelle Fuerst, to provide recipes and there you have it.
Our goal is three-fold: to share the fascinating biology of our food plants, to teach biology using edible, familiar examples, and to suggest delicious ways to bring the plants and their stories to your table. To judge by the questions we are often asked at dinner parties (“What is an artichoke?” “Why is okra slimy?”), some curious eaters genuinely want to know which plant part they are eating and how its identity affects the characteristics of the food.
Plants and food? Tell me more! Well, espousing the view that ‘a person can learn a lot about plants through the everyday acts of slicing and eating them’, The Botanist in the Kitchen ‘is devoted to exploring food plants in all their beautiful detail as plants – as living organisms with their own evolutionary history and ecological interactions’.
I first learned about the blog back in 2015 from an article in Business Insider, linking to their post on the various foods we grow, that were bred from one species of plant …
Six vegetables you can find in any grocery store and which most people eat on a regular basis are actually all from this one plant. Over the last few thousand years, farmers have bred Brassica Oleracea into six “cultivars” that eventually became many of the vegetables we eat …
Some species have undergone the domestication process multiple times, and with some of these species, each domestication effort has focused on amplifying different structures of the plant, producing a cornucopia of extraordinarily different vegetables or fruits from the same wild progenitor. Such is the case with Brassica oleracea. The wild plant is a weedy little herb that prefers to grow on limestone outcroppings all around the coastal Mediterranean region.
So if you enjoy learning about plants we eat, and trying various recipes with them, be sure to follow the Botanist in the Kitchen via email.
Previous posts here on the other blogs I’ve recommended:
Hybrid, heirloom, organic, non-GMO, natural….there’s lots of labels on those seed packets or plants you pick up at the garden center or from your favorite catalog. Since the seed-starting season is upon us, let’s take a minute to look at some of the information – and mis-information – you might find on those seed packets.
For a brief overview, here’s a short video segment I recently shot for the Backyard Farmer Show, a popular public TV offering for Nebraska Extension:
Hybrid vs. Heirloom vs. Open Pollinated
Just what is a hybrid anyway?
Simply put, a hybrid is a plant (or any living organism, technically) with two different parents. Take for example the Celebrity variety of tomato, which is very popular among home gardeners. In order to get seeds of Celebrity tomatoes, whoever produces the seeds must always cross two specific parent plants to get those specific seeds, called an F1 hybrid.
These parents have been developed through traditional breeding programs (read: the birds and the bees — no genetic engineering here) from many different crosses. Hybridization has occurred naturally ever since there were plants. Man has been directing this process throughout most of his agricultural history to get better crop plants. How else would we have many of the vegetables and fruits that we take for granted today?
Crops like corn have very little resemblance to its wild counterpart, many thanks to selection and even crossing of superior plants by humans over the centuries. University researchers and seed developers use this natural ability of plants to cross to direct the formation of new varieties that improve our ability to produce food.
What is an heirloom?
Perhaps the first question we should ask is, what is an open-pollinated seed? An open-pollinated variety is one whose genetics are stable enough that there is no need for specific parent plants, because the seeds produced from either self-pollination (as in the case of beans and tomatoes) or cross-pollination with the same variety will produce the same variety.
An “heirloom” plant is basically an open-pollinated plant that has a history, either through age (50-plus years) or through heritage (it has a family story).
Take for example the Mortgage Lifter tomato.
It was developed by a gentleman living in West Virginia (my native state -there are two competing stories as to who developed it). For all intents and purposes, the Mortgage Lifter started out as a hybrid, since the gardener in question developed the tomato by crossing many different varieties to find one that he liked. He sold so many of them to his neighbors that he was able to pay off the mortgage…thus its interesting moniker.
It just so happened that the genetics of this tomato were stable enough that its offspring had the same characteristics, so seeds could be saved. Therefore, it was technically an Open-Pollinated variety. Over time, the tomato became considered an heirloom because of both its age and unique story. This story has played out many times, in many gardens and in many research plots at universities.
There are some trying to revive the practice of plant breeding for the home gardener. If you’re interested, check out the book “Plant Breeding for the Home Gardener” by Garden Professor emeritus Joseph Tychonievich. Who knows? Maybe in 50 years we will be celebrating your plant as a distinctive heirloom.
So which is better – Heirlooms or Hybrids?
There are pros and cons to hybrid plants and heirlooms both, so there really isn’t an answer as to which one you should plant. It really boils down to personal choice. Hybrid plants tend to have more resistance to diseases and pests, due to the fact that breeders are actively trying to boost resistance. This means that there will be higher-quality produce fewer inputs. This is why hybrids are popular with farmers — nicer, cleaner-looking fruits with fewer pesticides. Many times hybrids are also on the more productive side, thanks to a phenomenon called hybrid vigor.
Heirlooms, on the other hand, help preserve our genetic diversity and even tell our cultural story. Heirlooms do not require a breeding program, so there is built-in resilience, knowing that we can produce these seeds well into the future with little intervention. But we do have a trade-off with typically less disease-resistance and less consistency on things like yield. Since they are open-pollinated, they are often a good choice for people who enjoy or rely on saving seeds from year to year.
GMO-Free or Non-GMO
As we have pointed out several times before, when it comes to seeds for home gardeners, the label of GMO-Free is largely meaningless and sometimes mis-leading. Whether or not you believe the prevailing science that shows that genetically engineered plants are safe for human consumption, you can rest assured that there are currently no genetically engineered seeds or plants available to home gardeners. Not on the seed rack at the box store nor your local garden center. Not in a catalog or online.
Here are two assurances to that statement: A majority of the things that you grow in the home garden don’t have a genetically engineered counterpart. Only
12 genetically engineered crops have been approved in the US, and only 10 of those are currently produced. Most of these are commodity crops that home gardeners would not even produce, such as cotton, sugar beet, canola, and alfalfa. A few more have counterparts that are grown by home gardeners, but are vastly different from those grown by commodity producers (soybeans vs. edamame soy). And some just aren’t that very widespread (there are some GE sweet corn cultivars and squash cultivars, but they aren’t widespread on the market).
So for the most part, there aren’t any “GMO” counterparts to the crops you’d grow in the home garden. They don’t exist.
The other assurance is that genetically engineered crops are not marketed or sold to home gardeners as a matter of business practice or law. In order to purchase genetically engineered seeds or plants, it is current practice in the United States that you must sign an agreement with the company that holds the patent stating that you will not misuse the crop or propagate it (and before we get into the whole intellectual property argument – plant patents and agreements like this have been around since the early 1900s – it isn’t new). So you know that you aren’t buying genetically engineered seeds since you aren’t being asked to sign an agreement. Plus, these companies make their money by selling large quantities of seeds, they just aren’t interested in selling you a packet of lettuce seeds for $2.
So since there aren’t any GMOs available to home gardeners, why do all these seed companies slap that label on their packets? Marketing, my dear! It started off with just a few companies, mainly using the label to compete in a crowded market. And fear sells. The label has spread to more and more companies as this fear and anti-science based marketing ploy has spread…both by companies who jumped on the fear bandwagon and by those who took so much harassment from the followers of the non-GMO crowd or they lost sales to people sold on the non-GMO label that they finally gave in. Unfortunately for some companies, slapping the non-GMO label on a product seems to give them permission to charge more, even if has no real meaning….so buyer beware.
Treated vs Non-Treated
Seed treatment usually involves the application of one or more pesticide such as a fungicide or insecticide to protect against pathogens or pests, mainly in the early stages of growth. A good example would be if you’ve ever seen corn, pea, or bean seeds at the local feed or farm store that are bright pink or orange in color. These seeds have been treated with a fungicide to offer short-term protection against damping off. Some crops are also treated with systemic insecticides, such as imidacloprid, to protect against insect damage. There’s been a big emergence of organic seed treatments, so treatment doesn’t necessarily mean the crop can’t be labeled organic.
Treated crops are most-commonly found at farm supply stores and aren’t generally marketed directly to home gardeners. You’ll likely not find them at most box stores or garden centers catering exclusively to gardeners. Many packets will specify whether they are non-treated or treated.
Organic and Natural
In seeds, the term Organic largely refers to seeds harvested from plants that were certified organic. Generally speaking, these seeds were produced on plants that received no synthetically produced fertilizers or pesticide sprays. However, it does not mean that the plants were not treated with pesticides. There’s a great misunderstanding about organic production – there are a number of pesticides and even seed treatments approved for use on organic crops. Typically, they are produced from a plant or microorganism extract, naturally occurring mineral, or other organic derivative. So organic does not equal pesticide free (on the seed rack or on the grocery shelf).
There are a few different levels of “organic,” too.
Sometimes small producers use the label in a general sense to mean that they follow organic practices, but aren’t certified. The process for certification is often onerous and costly for small producers, so they often opt to not get it. This is especially true for producers that market exclusively to a local clientele, like at the farmers market, where they can rely on their relationship with customers and reputation to speak for their practices. Some food companies may also use a simple “organic” label – either as a design choice, or because their product wouldn’t qualify for a certification.
“Certified organic” means that the producers practices have been certified to meet the requirements laid down by a certifying agency. A certifying agency could be a non-profit or a state department of agriculture. The requirements and practices vary from entity to entity.
For certified organic producers, a requirement for production is that all seeds or plant sources are organic. For home gardeners, I often question the need for organic seed, even if organic methods are followed. A quick literature search turned up no evidence that garden seeds contain pesticide residues. There’s been no evidence that plants translocate systemic pesticides to their seeds or fruits(Though it is impossible to prove a negative). Since seeds are located inside some sort of fruit, there would be little chance of residue on the seed from a pesticide application. And even if there was some sort of residue, it would be such a small amount in the seed that it would be so dilute in the mature plant that it would likely be well below any threshold of threat to human or wildlife health…or even measurability.
Personally, I may opt for the organic seed at home if it were the same price of the “conventional” on offer…but that organic label often includes a pretty good price differential. Knowing that there likely isn’t a huge difference in what is in the packages….my penny-pinching self will reach for the conventional, cheaper option.
And what about “natural.” That one’s easy….there is no recognized definition of natural by the USDA or any other body. Companies use that term to mean whatever they want it to mean….meaning that it is relatively meaningless in the grand scheme of things.
As we get close to the time to start tomato, pepper, and other seedlings indoors, I thought I’d share this picture of my older sister’s seed starting setup from few years ago:
Two desk lamps with compact florescent bulbs. Not traditional, but worked great. Just a reminder that you can get creative when it comes to lighting for seedlings, using whatever fixtures and layout works for your space. The only rules are to use florescent or LED bulbs, not those old fashioned incandescent bulbs which have poor light for plants, and err on the side of more light rather than less to make sure you get compact, healthy plants that will transition to the sunny outside world without drama.
As a beginning gardener I learned that to give plants like tomatoes and peppers more time to grow and produce the largest possible crop, it was best to start the seeds early indoors.
As soon as I learned that, I wondered: Well, if starting my tomatoes 6-8 weeks before transplanting them outside is good, surely 10 weeks would be better, right? Or 12? Or 16?
Turns out, earlier isn’t always better, and here are some of the reasons why.
First, you probably don’t have enough light. If, like most home gardeners, you are starting seeds under florescent bulbs, it is difficult to give sun lovers like tomatoes and peppers enough light. Light intensity drops off rapidly as you move away from the bulbs, so you know to keep the bulbs right above your seedlings. This works great when the plants are small, but as they grow it becomes very difficult to give both the tops and the bottoms of the seedlings enough light. The result is dying lower leaves and spindly, unhealthy growth.
Secondly, you are almost certainly going to get some crappy root systems. If you’ve followed this blog for a while, you’ve no doubt read Bert and Linda talking about all the potential problems with the root systems of container grown trees and shrubs. Well, most of the same problems develop with other plants grown in small containers. The roots start circling and they are slow to grow out of the rich soil of the container and into the native soil around them once transplanted into the garden. The longer your transplants grow indoors, the more likely they are to develop problematic root systems. Keeping transplanting them up to larger and larger containers can help mitigate the problem, but that quickly takes up far more space than most home gardeners have for there seedlings.
How big and impact that circling root system will have on the health of the plant varies by species. My personal experience growing zinnias, for example, is that they handle circling, pot-bound roots so poorly that plants from seeds sown directly in the garden quickly over-take and out-perform plants started weeks earlier indoors.
So follow the recommendations for the timing of seed starting. It really does work better. You should be able to get advice on when to start seeds from the catalogs you are shopping, extension offices, or you can use Margaret Roach’s excellent seed sowing calculator.
If you DO decide that earlier is better, that you can provide the light and generous pot sizes to avoid problems, there’s no harm in giving it a shot. But if you do, try starting a second batch at the later, recommended, time and growing the two side-by-side in the garden so you can really compare and see which perform best in the actual conditions of your garden, and if all that extra time and space under your lights or in your greenhouse was really worth it.
I believe I’ve spent approximately $1,000,000 on seeds over the years. Plant and seed catalogs are usually addressed to “Gullible L. Scoggins.” I really suffer (on many levels) during the darkest days of winter; this makes me highly susceptible to seed catalogs filled with delicious descriptions and enhanced photos.
This spring, I sorted through my massive bin of partially used seed packets and ruthlessly (ruthlessly!!!) chucked everything dated prior to 2012 (like normal people do). A large portion of the expired packets were for squash and zucchini. I love squash of every ilk – glossy dark zukes, gold crooknecks, pattypan-anything. Squash and tomatoes are summer incarnate.
My absolute favorite is the heirloom Italian variety Costata Romenesco with its dense, nutty flesh – it really tastes like something on its own. The huge rambling vines put out relatively few fruit, so not the best for a compact garden.
But variety is the spice of life…so how to try several varieties and not end up with either a mountain of squash (as happened to me a while back) or a bunch of seeds left over? California seed purveyor Renee’s Garden does a very cool thing – one pack of seeds with three (3!) varieties – the “Tricolor Mix”. Brilliant! You get a gold-bar type (Golden Dawn), the dark green one that will go berserk (Raven), and a lovely pale gray-green Clarimore.
The seeds are color-coded with just good ol’ food coloring, so you know what you’ve planted. I got 100% germination (whoops) and a delightful variety and volume of zucchini. And NO LEFTOVER SEEDS – so I will feel completely justified next February when ordering more. Hurrah!
I was checking my eggplants today, and watching the bumble bees getting busy with the large purple flowers. As they flew in, buzzing away, they landed on the flower and kept buzzing — but the note changed, dropping in pitch. The bumble bee hummed away for a while, then flew off to the next flower.
I was watching buzz pollination at work. Egg plants, and a lot of other flowers, don’t leave their pollen hanging out in the open where any ant or fly that happens by could eat it. Rather they wrap them up in little packages that, when vibrated at just the right rate by a buzzing bumble bee, sends the pollen shooting out, so that bumble bees, which pollinate effectively, can access the pollen, but other insects, that would just eat it all, can’t.
In the garden, it isn’t easy to catch a glimpse of the pollen spewing forth, but luckily there are videos. Thank goodness for youtube. Watch it, and next time you are in your garden and hear a bee land in the flower and suddenly change the tone of its buzz, know you are seeing — and hearing — buzz pollination at work.
With drought predicted for the west, southwest, and south through June 2015 (National Weather Service March 2015), many conscientious vegetable gardeners will try to conserve water by using soaker-hoses, those bumpy black hoses that weep water onto the soil through tiny pores.
Soaker hoses are made from fine-crumb rubber, usually recycled from vehicle tires. Research strongly establishes that tire particles leach heavy metals, carcinogens, and mutagenics, among other toxins. Yet soaker hoses have not been studied for potentially increasing the toxicity of edible plants. Are they really safe to use safe on our edible plants?
Soil in the City
Urban soils already contain high levels of heavy metals (Murray et al. 2011) from years of household runoffs—chemicals from pesticides, cars, painting, cleaning, and more. Adding soaker hoses made of crumb tires might exacerbate the problem.
Whether plants take up enough heavy metals to be toxic, however, is a complex equation, depending on a slew of interrelated factors, including:
• Soil pH (Costello 2003) and texture (Singh and Kumar 2006; Murray et al. 2011)
• Temperature (Murray et al. 2011; Lim and Walker 2009)
• The size of the rubber particles (Gaultieri et al. 2004)
• Chemical composition of irrigation water (Singh and Kumar 2006)
Furthermore, the plant species and even the cultivar can affect a plant’s uptake of zinc and other heavy metals (Murray et al. 2009 and 2011).
Growing Healthy Food
If you’re looking for the key to ensuring that your vegetable patch grows healthy food, however, I’m sorry to disappoint you. Too many factors are involved to predict the toxicity of what we grow in our gardens.
A good way to get more information is to contact your local extension agent for a list of laboratories that test soils not only for nutrient composition but for heavy metals. Although this information won’t guarantee you’ll be able to grow heavy-metal-free produce, it’s a step in the right direction while we wait for more research to be done.
Cindy Riskin is a Master of Environmental Horticulture and freelance journalist raising edible plants, an unkempt ornamental garden, and elderly mutts in Seattle, Washington.
NOTE: This article is excerpted from a longer one soon to appear in Cindy Riskin’s upcoming blog, tentatively named Muddy Fingers Northwest. Please contact Cindy Riskin at email@example.com for an advance copy or the blog’s web address.
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3. Lim, Ly, and Randi Walker. 2009. An assessment of chemical leaching releases to air and temperature at crumb-rubber infilled synthetic turf fields. Albany, N.Y.: New York State Department of Environmental Conservation. http://www.dec.ny.gov/docs/materials_minerals_pdf/crumbrubfr.pdf.
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Once you’ve chosen cover crops that fit your vegetable rotation, management goals, and garden site (See Part III: Selecting Cover Crops for Vegetable Gardens), it’s time to plant! This article contains tips on sourcing seed, and planting and managing cover crops using hand tools.