Finding good companion planting is even more important when the plants are stuck together in a container. I watched the denizens of assorted pots fight for dominance many a time and more often than not one species brazenly asserts its rights over the sun, water and nutrients and ends up owning the planter by the end of the summer.

If you don’t want to end up with a monoculture, here are a few compatible flower combinations.

For shade, a mix of impatiens, wax begonias, tuberous begonias and asparagus fern will maintain themselves in balance. For a sunny spot, sweet alyssum won’t mind sharing with most low growing annual flowers, like petunias, sweet williams, or stock. Cherry pie plant gets along with verbena and celosia, moss roses with petunias and snapdragons and nasturtiums with marigolds. Wishbone flowers with lobelia and petunias. Impatiens are nice to all the other plants.
I tried the following in mixed containers and they always end up owning the pot alone: lantana, silver miller, coleus, four o’clocks, zinnias and nicotiana.

I cheat. If I like a certain flower combination but I don’t want the plants to end up fighting each other to the death I plant them in separate containers and pack the containers tightly together. By the time their foliage starts to assert itself in mid summer it gets kind of hard to tell what grows where.

Author's Bio: 

Main Areas: Garden Writing; Sustainable Gardening; Homegrown Harvest
Published Books: “Terra Two”; “Generations”; "The Plant - A Steampunk Story"; "Letters to Lelia"; "Fair"; "Door Number Eight"; "A Year and A Day"; "Möbius' Code"; "Between Mirrors"; "The Blue Rose Manuscript"
Career Focus: Author; Consummate Gardener;
Affiliation: All Year Garden; The Weekly Gardener; Francis Rosenfeld's Blog

I started blogging in 2010, to share the joy of growing all things green and the beauty of the garden through the seasons. Two garden blogs were born: allyeargarden.com and theweeklygardener.com, a periodical that followed it one year later. I wanted to assemble an informal compendium of the things I learned from my grandfather, wonderful books, educational websites, and my own experience, in the hope that other people might use it in their own gardening practice.