We've been talking about what we plant and how and why, and I promised to start a thread on how different plants can be arranged together in the garden.
While I refer to the fenced, edible garden at our house as "the veggie garden", it is a true cottage-style garden, with flowers, fruits, herbs and vegetables all planted together. Sometimes it might look randomly planted, but each variety is planted where it is for a specific purpose.
On a different thread we discussed some of the various companion plants that can be used for different purposes...to attract beneficial insects including pollinators to the garden, to repel some pests from certain plants, to improve soil or to grow compost crops specifically to be harvested and put onto the compost pile, but the purpose of this thread is to talk about how we deliberately mix all those various things together along with the veggies, herbs and fruit that we grow to eat.
Essentially, when you are companion planting 2 or more different types of plants together, your intent is to put together different plants whose growth will assist or benefit each other. Or, at the very least, you're hoping they have a neutral affect on one another and do not negatively impact each other. You also are hoping that you will be getting the best use possible of the planting area that you have available to you.
I'll start by saying that variety is the spice of life, so that I don't plant the garden the same way every year. I'm always experimenting to see if option A works better than option B or if maybe option C is better than both A and B. Don't be afraid to experiment because you'll learn something from it one way or another.
What we often refer to as companion planting also is known as interplanting or intercropping. Many books bave been written on this topic, some based on traditional knowledge passed down from one generation to another and others based on research showing what works, how it works or even questioning whether it works. If the big question is "does companion planting work?" in terms of helping you have a better garden, then I guess the best answer is that it sometimes works. There's so many variables that it can be hard at times to know what is working or what isn't working particularly with our erratic weather.
INTERCROPPING: This involves planting 2 or more different edible crops together in the same space. You would do it for various reasons. Intercropping allows you to make better use of your space, can make it harder for some pests to find their favorite plants to eat, can help some plants by shading them from sun or by making it easier for them to germinate or whatever. Here's some examples:
RADISHES + CARROTS: Radishes have relatively big seeds that germinate quickly and the seedlings pop right up out of the ground in just a few days. Carrots, on the other hand, have tiny seeds that are slower to germinate. If your soil has dried out and crusted over as soil tends to do, sometimes the little tiny carrot sprouts cannot break through the soil surface so that they essentially try and fail, and the tiny seedlings die before they see the light of day. As you look at that bare spot of ground where carrots should be growing, you cannot know that they tried to sprout but couldn't break through the soil, so all you know is that your carrot seed didn't germinate. The issues with soil crusting over is more common in dry years than wet ones, but it can happen at any time.
You can interplant your carrot seed and radish seed together, just putting a radish seed in the ground every inch or two in the row or block planting of carrot seeds. The radishes will pop up first and loosen the soil, which helps make it easier for the carrots to sprout. Because spring radishes mature in just a few weeks (in as little as about 3 weeks), you carefully pull out the radishes, leaving more space for the carrots. As the carrots enlarge and grow, they'll fill in the space left behind by the removal of the radishes. This is an old traditional planting scheme that's been used for generations, and you've just gotten 2 crops out of space that otherwise would have given you only one.
RADISHES + CARROTS + LETTUCE: I often add lettuceto the radishes and carrots planting. The part of the radishes and carrots we eat are below ground, leaving lots of useful space above ground. The part of the lettuce we eat that grows above ground can expand that space. Obviously you don't want to plant too much lettuce too close to radishes or carrots because you don't want to shade them out, but the three can be successfully grown in unison.
LETTUCE + ANY TALLER PLANT: Lettuce is pretty much neutral. It will benefit from being grown in partial shade provided by any taller plant because heat will make lettuce bolt. Keeping it partially shaded keep it cooler Lettuce doesn't really hurt anything, and it makes a lovely ground cover that will shade the ground under taller plants. By shading the ground, it cools the soil, reduces the evaportation of water from the soil and inhibts weeds from sprouting. I am not saying the weeds won't sprout, but with lettuce plants cutting off the sunshine to the ground, the weed seeds maybe won't get as much sun and heat as they need to sprout, or they'll struggle to compete with the lettuce. If you weed early and often while the lettuce is small, it won't be weedy and you'll have a lot less weeding to do after the plants gain some size.
SPINACH + BIBB LETTUCE: Planting spinach and bibb lettuce together is another traditional planting scheme. I don't know why, and I don't know if scientists even yet can explain it, but bibb lettuce grows better when interplanted with spinach.
We know that with some companion plants, exudates from the root of one plant can pass into the root zone or the actual root of the other plant, perhaps benefitting the plant in some way by making it grow better or repel insects or whatever, but I don't know if anyone knows why bibb lettuce grows better when it is interplanted with spinach in close proximity. I think the most commonly used ratio is one spinach plant for every four lettuce plants.
POTATOES + BUSH BEANS: The theory behind planting these two together is that the potatoes protect the beans from Mexican bean beetles and the beans protect the potatoes from Colorado Potato Beetles. I think it works, but I don't think it is easy to achieve this. I have problems with the potato plants outgrowing the bush beans and shading them out if I plant the potatoes too close to the bush beans. And, by the way, pole beans don't confer the same protection on the potatoes as the bush beans do. The first time I did this, I tried to alternate, planting one square foot of potatoes, then the next square foot of beans. All I got was bean plants that were too shaded by the taller potato plants to produce well, but I didn't see any potato bugs or bean beetles. The next year, I planted the potatoes in the north half of the bed and the beans in the southern half. It was a long rectagular bed that ran east-west. That worked out better. In between the two I planted a row of petunias, because traditionally it is believed that potatoes grow better when grown with petunias. All of that seemed to work out really well. As a further Colorado Potato Beetle deterrent, I planted 4 horseradish roots into 2 gallon pots and sunk them into the ground so they looked like they were growing in the ground. I had one at each corner of the bed. Horseradish is said to repel Colorado Potato Beetles. However it is very invasive, which is why it was in pots. You also can add several dead nettle plants and flax plants to your potato bed as both are to repel CPBs, and to improve their growth and flavor. The flax and dead nettle also likely attract beneficial insects. You can tuck a few marigold seedlings into this bed with everything else because marigolds are said to repel Mexican bean beetles. Obviously you should have the marigolds closer to the beans than to the potatoes. Rosemary also is said to repel Mexican bean beetles so you can put one of these plants into the groundin this bed. Watch your plants as they grow and you'll see many beneficial insects moving from one flower or herb plant to another. All of the insect activity will help keep down the number of pests you spot.
THE THREE SISTERS....OR MAKE IT 4 OR 5 SISTERS: The native tribes who lived in North America long before the white men arrived here traditionally grew the three sisters: corn, beans and pumpkin (winter squash) together, although they didn't necessarily grown them in the same way. Each tribe, or maybe I should say the various tribes in each region, altered the planting layout to suit their climate and soil. The reasons behind planting these together are interesting. Corn, which loves nitrogen, is a heavy feeder. Beans, as with all legumes, fix nitrogen from the air so that they can return it to the soil over time (but only if you incorporate the plants into the ground after you've harvested all the beans). So, your beans are going to put nitrogen back into the soil to help make up for all the nitrogen the corn took out of the soil. This is crop rotation over time. What is the purpose of the pumpkins or winter squash? They are large sprawling plants that will shade the ground beneath the corn and beans, serving as a living mulch that reduces weeding by shading out weeds and that keeps the ground more moist by blocking the rays of sunlight from hitting the ground. Best of all, the big coarse pumpkin or winter squash leaves often are somewhat prickly and it is believed they help keep the raccoons out of the corn. I have found that sometimes they keep the raccoons out of the corn and sometimes they don't, but I plant them together anyway. It is a great use of space, giving you at least three different veggies from space normally used for one.
In order to make this work in our modern gardens, we have to tweak it a little bit. The types of corn traditionally grown by the native Americans, depending on their geographic location, tended to be dent corn, flour corn or field corn. These types of corn grow taller and sturdier than most of our modern day sweet corn varieties, which tend to be wimps by comparison. I find it somewhat problematic to plant most varieties of modern day corn with pole beans as the weight of the pole bean plant can pull down the corn plants. You can do it, though, if you choose a really strong, sturdy variety of sweet corn. I like to do it with Texas Honey June which is a monstser plant that often gets 8-9' tall in my garden. I'd never try it with a small variety like Early Sunglow. Sometimes the vines twine around the ears as they are growing and impede their growth. So, while I love to plant three sisters style, I will alter it a little bit. Sometmes I will plant my beans on the garden fence adjacent to the corn planting. I might plant it on one or two of the four sides of the pen, Then I'll plant the pumpkins. It helps to plant the corn first and let it make some growth and achieve some height first so the winter squash or pumpkin doesn't shade it while it is too young. This is pretty easy to do because corn can go into cooler soils than winter squash can. So, if you just naturally plant your sweet corn at the right temperatures, then by the time the soil warms up enough to plant winter squash or pumpkins, the corn plants will be gowing nicely and too tall for the squash to shade them out. I usually plant the corn first, the pole beans 2 or 3 weeks later, and then the squash a few weeks after that.
How about a fourth or fifth sister? Because I sometimes grow my corn in a corn cage (picture a dog kennel type pen with a chicken wire fencing roof to completely exclude raccoons), I have fencing on all four sides of the corn patch. So, I'll come back and plant a pole type of lima bean (like Worchester Indian Red or Christmas Pole) or southern pea (like Red Ripper/Mandy) on the other two sides. Last year I planted Yard-long Bean on the fence alongside one side of my mid-season corn patch. Since they are legumes, they'll give back to the soil just as the beans will. The fifth sister I plant is sunflowers, which also are traditionally grown as a fourth sister by many native American tribes. I didn't know that until I read the utterly fascinating book "Buffalo Bird Woman's Garden". Sometimes I plant edible golden purslane or the ornamental flowering purslane on the ground just on the edge of the garden kind of between the fence with its legumes growing on it and the first row of corn. Along with the pumpkins it serves as a living mulch to help keep down weeds, but it is so small it doesn't compete and steal water away from anything else. The flowers attract beneficial insects, as do the flowers of the sunflowers. I also like to have a small patch of buckwheat near the winter squash and corn. Buckwheat flowers pretty early from seed--in about 5 or 6 weeks, and the flowers attract lots of the types of beneficial insects that attack corn and squash pests. The buckwheat can be pulled later on and put on the compost pile, pulled and laid on the ground where it will serve as a mulch until it decomposes, or can be dug into the soil or rototilled into it at the end of the season.
One of the biggest challenges with a Three (or more) Sisters Garden will be how to harvest the ears of corn or the beans without breaking the squash plants. I just try to watch where I put my feet and hope that if I step on the squash plants, they'll forgive me. I usually just leave the bean and corn plants in the ground after I harvest from them. Sometimes the beans meander over from their fence/trellis and climb on bean plants and I just let them. Sometimes the winter squash or pumpkin plants do the same thing. No harm, no foul. Last year, I crammed leftover okra plants down at one end of my five-sisters garden, with a few ornamental gourds on the fence at that end so I had a Seven Sisters garden in a space where some people only would have planted corn. It is your garden. If you want to grow multiple plants in the same area, do it. Does Mother Nature have all of one kind of plant in one corner of a field, and something else in another isolated spot? No. They all grow together and benefit one another in various ways.
TOMATOES: It is tempting to just plant your rows of carefully spaced tomato plants all in big beautiful rows and call it a day. That way nothing else is in the way when you're picking tomatoes. But....it is so boring, and there's nothing growing there around the tomato plants to help them. When you grow in a monoculture, you invite both diseases and pests that feed on the monocultured crop to come have a feast. Instead, you can create a polyculture and sow carrot, radish and lettuce seeds to grow in the shade of the tomato plants. To do that, I usually plant the lettuce, carrots and radishes first, leaving an open spot periodically where I'll come along later and plug in the tomato transplants. The carrots, radishes and lettuce all will be done and out of there almost before the tomato harvest begins, except with the earliest tomato varieties. The lettuce will benefit from being shaded by the tomato plants as they grow and the shade may keep them from bolting quite as early once the air temps are getting hotter than the lettuce likes.
I like to plant basil and borage with the tomato plants. I just stick one in the ground every few feet. Basil is said to improve the growth and flavor of tomatoes and borage is said to help repel tomato horn worms, which I happen to believe as I seldom see any tomato or tobacco hornworms in my garden even though I grow tons of tomatoes and quite a few flowering tobacco (nicotiana) plants. I plant chervil and chives along the wooden edge of the beds, where they help repel pests and/or help attract beneficial insects. Chives are said to improve the growth and flavor of carrots while chervil performs the same function for radishes. Mint is said to improve the health and growth of tomatoes, but I'd never put an invasive plant like mint into the ground near my tomatoes, to I put it in pots near them. I usually add a few nasturium plants to any bare spot in the bed, and do the same with the The Three Sisters Garden. Nasturtiums attract many beneficial insects and improves the growth and flavor of the radishes. Over in the Three Sisters Garden, the nasturtiums will repel squash bugs, aphids and striped cucumber beetles (which attack all cucurbits and most any other plant they find as well).
Because I plant several raised beds of tomato plants, I vary my companion plants a lot. I will add green onions (to be harvested as scallions), parsley, and chives to some beds. I'll add short, compact zinnias and sweet alyssum to attract beneficial insects. If I put onions in a tomato bed, I'll interplant the onions with chamomile because it is said to improve their growth and flavor. I'll plant white-flowered borage in some tomato beds and blue-flowered borage in others. I'll use different types of bush nasturstiums to different tomato beds. Sometimes I plant marigolds, but I am careful about which kind I select. Some of them will attract spider mites, which are a major problem in my rural area. They literally blow in on the wind and that makes them more difficult to fight. Often, they will congregate on marigolds. If that happens, once the marigolds have a lot of spider mites, I sacrifice them as a trap crop, pulling them up and bagging them and trashing them in order to get rid of the spider mites. More mites will come later, but at least I've taken out all of that bunch of spider mites.
CUCUMBERS can be grown in your three sisters garden if you have space, but I usually plant them alone near a trellis or garden fence they can climb. They like to grow with sunflowers, so I plant a sunflower every 2 or 3 feet. You also can underplant your cukes with radishes or lettuce or both. I like to get a lot of cucumbers at one tine in pickling years so I can make many batches of pickles, and then not worry about pickles again for a year or two. I usually grow my cucumbers on the north garden fence bordering the woods because the pests are slower to find them there than if I grow them on the south garden fence near the driveway. I used to grow tansy inside the garden as it attracts many beneficials and repels some pest insects, but it is a rampant grower and was hard to control. Nowadays I plant it outside the fenced garden in the space between the north garden fence. It is a good companion for cucumbers grown there because it deters cucumber beetles, which surely are the bane of a cucumber grower's existence as they spread disease. I usually plant nasturtiums at the feet of the cucumber plants to both serve as a living mulch and to attract beneficials. You also can grow peas, beans, lettuce or radishes with your cukes. I like to plant rat-tail radishes near all members of the cucurbit family because their flowers attract beneficial insects that prey upon some pests of the cucurbits.
EDIBLE PODDED PEAS + ROOT CROPS + sweet alyssum. Sugar snap peas and snow peas are two of the earliest crops to go into the garden. If you plant the vining kind and let them climb a fence or trellis, you can underplant them with turnips or rutabagas planted at about the same time (or even a little earlier), or you can underplant them with nasturtiums or buckwheat. The nasturtiums and buckwheat attract beneficial insects that will help control pest insects like pea aphids.
ASPARAGUS + TOMATOES are said to be good companions to one another, but I don't interplant them. My asparagus is in a bed more or less by itself because it is a perennial crop and I don't want to disturb it. Last year, Laura Bush petunias (which live all summer and laugh at the heat and then reseed themselves too) popped up in the aspargus bed so I thinned out most of them, but let some stay as a living mulch to keep the soil cool and shaded. That seemed to work out pretty well. I did grow tomato plants in their own bed next door to the asparagus though. I also had a row of parsley down one side of the bed along the wooden edging and a row of basil down the other long side of the bed along the wooden edging.
OKRA + WATERMELONS: I use fairly wide spacing with the okra plants when I use branching varieties and underplant them with watermelons. It is just a good way to get more use from the space, and the watermelons shade the ground and serve as a living mulch for the okra and the okra helps shade the melon fruit and keep them from sunburning. It seems to be a mutually beneficial relationship. I usually have a few zinnias and nasturtiums in that bed, along with some flowering nicotines. If you've never grown nicotianas, you may not realize that the backs of their leaves are sort of sticky and insects can become stuck to those leaves....like a natural form of flypaper. I've grown these plants together for several years and they seem to grow as well together as they do apart.
CABBAGE FAMILY CROPS: (cabbage, broccoli, cauliflower, kale, kohlrabi). The types of plants I interplant with these are chosen for their ability to repel the dreaded broccoli worms. For this purpose I interplant with chamomile, dill and sage. If I have leftover onion plants (bulbing or green onions), I'll put one in the bed here and there. You can add any sort of aromatic plant known to repel moths, which includes chamomile, dill, sage, rosemary, and thyme. There are some other plants known to repel moths but you have to handle them differently. All mints are repellents, but are very invasive, so I have them nearby in pots. Wormwood is an excellent deterrent, but I like to plant it about 3' away, outside the garden fence if possible, because it has root exudates that can have an alleopathic effect and negatively impact the root growth of desirable plants. If the cabbage family plants are in the middle of the garden, I just put a few wormwood plants in pots near them. I like to leave a lot of my permanent herbs in pots, so I can move them around the garden every year without digging them up.
BEETS + ONIONS -- both are root crops, both go into the ground early, and they seem compatible with one another. Otherwise, I don't interplant too much with the main bulbing onion crop. They really don't like competition from weeds or from other interplanted crops, so I leave them alone for the most part, although every now and then I'll put a little sweet alyssum plant here or there to attract beneficial insects. I've never really had a problem with pests on onions, and if you have an issue in your garden with western flower thrips, I would keep all flowers away from the onions.
EGGPLANT grows well with potatoes or with beans, but I don't grow a lot of eggplant because no one in my family especially likes to eat it. Sometimes in the past I also companion-planted it with hot peppers and they seemed to peacefully co-exist with one another and with nasturtiums really well.
PUMPKINS + CORN, ETC. About the only way I ever grow pumpkins and winter squash is with corn. They grow just fine by themselves too, but I always like to grow buckwheat and nasturtiums around them to attract beneficial insects.
SUMMER SQUASH: These are such big sprawling plants that I don't really plant much else with them as an edible compaion, but I like to plant buckwheat, nasturtiums and rat-tail radishes with them. Actually, I usually plant the nasturtiums, rat-tail radishes and buckwheat first, and then transplant the squash plants into the ground (you can direct-seed them if you prefer). I feel like the companion plants need to be up and growing fast so they can attract beneficials as the squash grows. Since squash grows so fast, plant the companion plants a little further away so they won't be buried under the squash plants.
PEPPER PLANTS + OKRA: Okra is tall, peppers are medium-high. Okras love sunshine, peppers like some sunshine but suffer mightily if they are in full sun in our hot summers from sunup to sunset. I usually plant my okra and pepper plants together, letting the okra plants shade the peppers. Of course, I usually have a few herbs and flowers in the bed with them....often nasturiums early in the season, but dwarf zinnias and Laura Bush petunias later in the season as the nasturtiums sort of falter in the heat. I also often plant basil and parsley in the same bed with them.
SOUTHERN PEAS: These are almost always treated as succession plants in my garden, often going into the ground in May or early June to replace earlier crops like broccoli, snap peas, spinach, kale, etc. Being heat-loving legumes, they are happy pretty much anywhere. I especially like to plant them in any bed from which I've just removed heavy feeders (pretty much everything we like to eat except for root crops are heavy feeders). I try to plant the southern peas in beds where no beans or peas grew the year before. My garden is very large, so it isn't hard to rotate legumes into beds where no legumes were grown recently. Last year I grew legumes on one portion of the north fence, and muskmelons and cuckes on another portion of the garden fence, so for crop rotation, this year I simply grow the legumes where last year's cucurbits grew and will plant the cucurbits in the area where last year's legumes grow. I don't drive myself crazy trying to maintain the heavy giver, light feeder, heavy feeder cycle because when you intercrop a lot, it is almost too much to keep up with. Anyway, since I garden organically and work continually to add compost and other organic matter to the soil, I don't think the giver-taker rotation is a critical as it otherwise would be.
Well, I'm sure I failed to mention some sort of crop, but I'm tired of typing and anyone who's made it this far is likely tired of reading.
For those of you who had questions about how to interplant to create a garden that is its own little ecosystem of plants who help one another, I hope this post gives you food for thought. For the many types of companion plantsing that I didn't specifically mention, I just routinely scatter them around the entire garden. There's really no wrong place, for example, to plant lemon balm or Mexican mint marigold.
Got questions? I'm ready.
I'm not going to go back and proofread for errors, so forgive any typos.