Garden Tower Project* > Most Popular > Companion Planting Reference Guide: How and WhyGarden Tower Project* > Most Popular > Companion Planting Reference Guide: How and Why

Companion Planting Reference Guide: How and Why

Companion Planting Guide Resource Page
Garden Tower Project* > Most Popular > Companion Planting Reference Guide: How and Why

Companion Planting Reference Guide: Why and How?


Companion planting allows you to select plants that benefit each other in a number of different ways; moreover, many common garden plants have allelopathic effects which means they can slow the growth of certain types of neighboring plants! 

Companion Planting Guide Resource Page

The composting vertical Garden Tower is the definition of a companion planting system — 50 plants in 4 square feet at six elevations guarantees plant-to-plant interactions at the stem and root levels. 

Here’s a fantastic go-to infographic to quickly reference for a reasonable understanding of which vegetables will thrive near to each other and which veggies you need to put a little space between:

(Click the image below for the readable full-resolution version!)

Companion planting infograhic for organic gardening

This infographic is from

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Afristar Foundation develops educational resources for schools, community programs and adult education in the form posters, educational documentaries and informational booklets. We make use of accessible media to illustrate techniques and principles of sustainability and to spread information in a manner that is fun, colorful and easy to understand.  To learn more visit


If you want to take this concept further — read on:

The following tables offer valuable insights for plant selection and design in a Garden Tower or conventional garden. 

Determine what plant(s) you would like to grow, check the table to learn which companion plants will help your desired plant thrive and which plants you should avoid planting adjacent to it!  Don’t be intimidated, it’s simpler than it looks! (use Firefox browser for the largest text!)

Vegetables: (Jump to Herbs or Flowers)

Common nameScientific name
HelpsHelped byAttractsRepelsAvoidComments
AlliumsAlliumfruit trees, nightshades (tomatoes, capsicum peppers, potatoes), brassicas (cabbage, broccoli, kohlrabi, etc.) carrotscarrotsslugs, aphids, carrot fly, cabbage worms[1]beans, peas, parsleyAlliums include onions, garlic, leeks, shallots, chives, and others
AsparagusAsparagus officinalisTomatoes[2]Aster Family flowers, Dill, Coriander, Tomatoes, Parsley, Basil, Comfrey, Marigoldscoupled with Basil seems to encourage lady bugsOnion, Garlic, Potatoes
BrassicasBrassicapotatoes, cereals (e.g. corn, wheat)geraniums, dill, alliums (onions, shallots, garlic, etc.), rosemary, nasturtium, boragewirewormsmustards, nightshades (tomatoes, peppers, etc.)Brassicas are a family of species which include broccoli, cabbage, Brussels sprouts, kohlrabi, and cauliflower.
BeansPhaseolusCorn (see Three Sisters), Spinach, lettuce, rosemary, summer savory, dill, carrots, brassicas, beets, radish, strawberry and cucumbersEggplant, Summer savouryCalifornia beetlesTomatoes, chili peppers, alliums (onions, garlic, etc.), brassicas (cabbage, broccoli, etc.)Hosts nitrogen-fixing bacteria, a good fertiliser for some plants, too much for others
BeetsBeta Vulgarislettuce, kohlrabi, onions and brassicasCatnip, Garlic, MintRunner or pole beans[2]Good for adding minerals to the soil through composting leaves which have up to 25% magnesium. Runner or pole beans and beets stunt each other’s growth.
BroccoliBrassica oleraceageraniums, dill, alliums, rosemary, nasturtium, boragemustards, Tomatoes, peppersRosemary repels cabbage fly, geraniums trap cabbage worms, same general companion profile as all brassica (cabbage, kohlrabi, Brussels sprouts, cauliflower, etc.)
CabbageBrassica oleraceageraniums, dill, alliums, rosemarymustards, Tomatoes, peppers strawberries, and pole/runner beansRosemary repels cabbage flies, geraniums trap cabbage worms, same general companion profile as all brassica (cabbage, kohlrabi, Brussels sprouts, cauliflower, etc.)
CarrotsDaucus carotaTomatoes, Alliums (onions, chives, etc.), lettucealliums (leeks, shallots, etc.), rosemary, wormwood, sage, beans, flaxassassin bug, lacewing, parasitic wasp, yellow jacket and other predatory waspsDill, parsnip, radishTomatoes grow better with carrots, but may stunt the carrots’ growth. Beans (which are bad for tomatoes) provide the nitrogen carrots need more than some other vegetables. Aromatic companion plants repel carrot fly. Alliums inter-planted with carrots confuse onion and carrot flies.
CeleryApium graveolensCosmos, Daisies, Snapdragonscorn, Aster flowers, these can transmit the aster yellows disease
Corn / MaizeZea maysbeansSunflowers, legumes (beans, peas, etc.), peanuts, cucurbits (squash, cucumbers, melons, etc.), amaranth, white geranium, lamb’s quarters, morning glory, parsley, and potato[2]Tomato, CeleryProvides beans with a trellis, is protected from predators and dryness by cucurbits, in the three sisters technique
CucumberCucumis SativusNasturtiums, radishes, marigolds, sunflowers, peas, beets, carrots, and DillBeneficial for ground beetlesTomato, Sage
Common nameScientific nameHelpsHelped byAttractsRepelsAvoidComments
Eggplant or AubergineSolanum melongenaBeans, PeppersMarigolds, tarragon, mintsMarigolds will deter nematodes.
LeekAllium ampeloprasum v. porrumCelery, apple treescarrotscabbage worms, aphids, carrot fly, othersLegumes (beans, peas, etc.), Swiss chardSame companion traits as all alliums (onions, garlic, shallots, chives, etc.)
LettuceLactuca sativaRadish, Kohlrabi, beans, carrotscelery, cabbage, cress, parsleyMints (including hyssop, sage, and various “balms”) repel slugs, a bane of lettuce and cabbages
MustardBrassicaceae, Sinapis albaCabbage, cauliflower, radish, Brussels sprouts, turnipsvarious pestsSame general companion profile as all brassica (cabbage, kohlrabi, Brussels sprouts, cauliflower, etc.)
NightshadesSolanaceaecarrots, alliums, mints (basil, oregano, etc.)beans, black walnuts, corn, fennel, dill, brassica (broccoli, cabbage, cauliflower, etc.)Nightshade plants include tomatoes, tobacco, chili peppers (including bell peppers), potatoes, eggplant, and others
Common nameScientific nameHelpsHelped byAttractsRepelsAvoidComments
OnionAllium cepaTomatoes, brassicas (broccoli, cabbage, etc.)Carrotsaphids, carrot fly, other pestsBeans, lentils, peas, parsleySame companion traits as all other alliums (chives, garlic, shallots, leeks, etc.)
PeppersSolanaceae, Capsicumthemselves, marjoramtomatoes, geraniums, petuniasTomato Hornwormbeans, kale (cabbage, Brussels sprouts, etc.)Pepper plants like high humidity, which can be helped along by planting with some kind of dense-leaf companion, like marjoram and basil; they also need direct sunlight, but their fruit can be harmed by it…pepper plants grown together, or with tomatoes, can shelter the fruit from sunlight, and raises the humidity level.
PotatoSolanum tuberosumHorseradishAtriplex, carrot, cucumber, onion, raspberries, squash, sunflower, tomatoHorseradish increases the disease resistance of potatoes
ParsnipPastinaca Sativafruit treesa variety of predatory insectsThe flowers of the parsnip plant left to seed will attract a variety of predatory insects to the garden, they are particularly helpful when left under fruit trees, the predators attacking codling moth and light brown apple moth. The root also contains Myristricin, which is toxic to fruit flies, house flies, red spider mite, pea aphids.
Pumpkin and other SquashCurcurbita sppcorn, beansBuckwheat, catnip, tansy, radishesSpiders, Ground BeetlesRadishes can be used as a trap crop against flea beetles, Curcurbita can be used in the three sisters technique
RadishRafanus Sativussquash, eggplant, cucumber,[2] lettuceflea beetles, cucumber beetlesRadishes can be used as a trap crop against flea beetles
SpinachSpinacia oleraceaPeas, BeansThe peas and beans provide natural shade for the spinach
TomatoesSolanum lycopersicumroses, peppers, asparagusbasil,[3] oregano, parsley, carrots, marigold, Alliums, celery, Geraniums, Petunias, Nasturtium, Borage, any type of onion or chivesTomato Hornwormasparagus beetleBlack walnut, corn, fennel, peas, dill, potatoes, beetroot, brassicas (kohlrabi, cabbage, etc.), rosemaryDill attracts tomato hornworm.

Growing basil 10 inches apart from tomatoes can increase the yield of tomatoes by about 20%.[3]




Common nameScientific nameHelpsHelped byAttractsRepelsAvoidComments
BasilOcimum basilicumtomato,[3] peppers, oregano, asparagus, petuniaschamomile, anisebutterfliesasparagus beetle, mosquitoes, thrips and fliescommon rueis said to make tomatoes taste better, chamomile and anise are supposed to increase the essential oils in many herbs like basil
BorageBorago officinalisAlmost everything, especially strawberry, cucurbits (cucumber, gourds), tomatoes and cabbagePredatory insects, honeybeesmany pestsPredict a square meter for its adult size. Borage is the magic bullet of companion plants
CarawayCarum carviStrawberriesParasitic wasps, parasitic flies
ChamomileMatricaria recutitaBasil, Wheat, Onion, Cabbage, CucumberHoverflies, waspsGrowing near herbs will increase their oil production.
ChervilAnthriscus cerefoliumRadish, lettuce, broccoliaphidsradishloves shade, fortunately it grows well with shade-tolerant food plants; will make radishes grown near it taste spicier
Cilantro / CorianderCoriandrum sativumspinachbeans, peastachinid flyaphids, spider mites, white flies and potato beetle
ChivesAllium schoenoprasumApples, carrots, tomatoes, brassica (broccoli, cabbage, mustard, etc.), many otherscarrotscabbage worms, carrot fly, aphidsbeans, peasSame companion traits as all alliums (onions, garlic, shallots, leeks, etc.)said to prevent apple scab after 3 years planting at base of apple trees
Common nameScientific nameHelpsHelped byAttractsRepelsAvoidComments
DillAnethum graveolensCabbages, Corn, Lettuce, Onions, CucumbersTiger Swallowtail butterflies/ caterpillars, Hoverflies, Wasps, Tomato Hornworm, honeybees, Ichneumonid WaspsAphids, spider mites, squash bugs, cabbage loopercarrots, tomatoesone of the few plants said to grow with fennel
FennelFoeniculum vulgareDillDillladybugs, syrphid fly, tachinid flyaphidsAlmost everythingFennel is allelopathic to most garden plants, inhibiting growth, causing to bolt, or actually killing many plants
GarlicAllium sativumApple trees, Pear trees, Roses, Cucumbers, Lettuce, CeleryAphids, cabbage looper, ants, rabbits, cabbage maggot, vampiresBeans, cabbages, peasDeters rabbits, same companion traits as all alliums (onions, chives, shallots, leeks, etc.)
HempCannabis sativa L. subsp. sativaBrassica (cabbage, brussels sprouts, other kales)Repels many types of beetles which attack cabbages.
HyssopHyssopus officinalisCabbage, grapeshoneybees, butterfliesCabbage moth larvae, Cabbage ButterfliesStimulates growth of grapes.
LovageLevisticum officinaleAlmost all plantsbeansIchneumonid Wasps, ground beetles (good)rhubarbIs thought to improve the health of almost all plants, like borage and geraniums, is considered a “magic bullet” of companion planting
OreganoOriganum vulgareTomatoes, peppers, many other plantsbasilaphidsprovides ground cover and much-needed humidity for pepper plants if allowed to spread among them
ParsleyPetroselinum CrispumAsparagus, corn/maize, tomatoesSwallowtail Butterflies, wasps, fliesAlliums, lettuceSacrificially attracts insects that predate upon tomatoes
Common nameScientific nameHelpsHelped byAttractsRepels
PeppermintMentha piperitaBrassica (cabbage, kholrabi, broccoli, and the other kales)cabbage fly, ants, cabbage looperRepels cabbage flies, has same general companion properties as other mints
RosemaryRosmarinus officinalissage, cabbage, beans, carrots, thymebean beetlebasilDeters cabbage flies, repels many bean parasites
SageSalvia officinalisrosemary, cabbage, beans, carrotshoneybees, cabbage butterflycabbage flies, carrot fly, black flea beetle, cabbage looper, cabbage maggotDeters cabbage flies, repels many bean parasites
Southern- woodArtemisia abrotanumFruit treesControls cabbage moths and malaria mosquitoes.
SpearmintMentha spicataants, aphidsControls ants and aphids, has same general companion properties as other mints.
Summer SavourySatureja hortensisGreen beans, onions,also delays germination of certain foul herbs
TansyTanacetum vulgarebeans, cucurbits (cucumbers, squash, etc.), corn, roseshoneybeesflying insects (Ichneumonid Wasps), Japanese beetles, striped cucumber beetles, squash bugs and antsIs reputed to generally repel insects (except for nectar-eating types). This herb should not be consumed, as it is quite toxic.
TarragonArtemisia dracunculusEverything, but especially eggplantIts scent is disliked by most pests, and this plant is also thought to have Nurse Plant properties, enhancing the growth and flavor of crops grown with it.
ThymeCabbage and broccoliDeters white fly




Common NameScientific NameHelpsHelped byAttractsRepels
GeraniumsPelargonium spp.Roses, corn, peppers, grapesleafhoppers, Japanese beetlesTomatoes, Tobacco, Eggplants and other nightshadesA trap crop, attracting pests away from roses and grape vines, distracts beet leafhoppers, carrier of the curly top virus, keep away from Solanaceous plants like eggplant, and tobacco
LupinLupinusCucurbits, brassica, lettuce, rosemary, dill, strawberrysummer savoryHoneybeestomatoes and other solanaceaeThis wildflower is a legume, hosting bacteria that fixes nitrogen in the soil, fertilizing it for neighboring plants
MarigoldAsteraceae Calendula Tagetesmost plants, especially tomatoes and peppers, cucurbits (cucumbers, gourds, squash), brassicas (broccoli, kale, cabbage)snailsnematodes, beet leaf hoppers, other pestsMarigolds are a wonder-drug of the companion plant world, invoking the saying “plant them everywhere in your garden”. French marigolds produce a pesticidal chemical from their roots, so strong it lasts years after they are gone. Mexican marigolds do the same, but are so strong they will inhibit the growth of some more tender herbs. Certain Varieties of marigolds (Tagetes) can help manage eelworms (Root-knot nematode) when planted the year before [1].

Tagetes has also been found effective against perennial weeds such as Ranunculus ficaria (Celandine), Aegopodium podagraria (Ground elder), Glechoma hederacea (Ground ivy), Agropyron repens (Couch grass), Convolvulus arvensis (Field bindweed), Equisetum arvense (Field/Common Horsetail) and other ‘starchy’ weeds.[citation needed]

PetuniaPetunia x hybridacucurbits (squash, pumpkins, cucumbers), asparagusleafhoppers, Japanese beetles, aphids, asparagus beetleIs a trap crop almost identical to geraniums in function
NasturtiumTropaeolum majusMany plants, especially cucurbits (melons, cucumbers, gourds), beans, tomatoes, apple trees, brassicas (broccoli, cabbage, etc.), radishpredatory insectsaphids, cabbage looper, squash bug, white fly, cucumber beetlesradish, cauliflowerBoth work as trap crops for aphids, is among the best at attracting predatory insects[citation needed]
SunflowerHelianthus annuuscorn, tomatoesaphidsWas grown as a companion for corn(maize) before modern Europeans arrived in the Americas, supposedly increases their production, ants herd aphids onto sunflowers, keeping them off neighboring plants
TansyTanacetum vulgarecucurbits (cucumbers, squash, etc.), raspberries and relatives, roses, cornsugar ants, Japanese beetles, cucumber beetles, squash bugs, miceToxic to many animals, don’t plant it where livestock browse
YarrowAchillea millefoliummany plantspredatory wasps, ladybugs, hoverflies, damselbugsMay increase the essential oil production of some herbs. Also improves soil quality, use the leaves to enrich compost, or as mulch.
ZinniaZinniabeans, tomatoes, pepperswhitefliesAttracts hummingbirds that eat whitflies, attracts pollinators







Source: Modified From:

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