7 Tips for Planting Flower Pots That Thrive all Season

These easy, tried-and-true tips and techniques for planting flower pots organically will help your containers grow, bloom, and look great all season long.

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Do you spend money and time in the spring planting flower pots, hanging baskets, or other containers only to have them look yellowed, limp, and sad by mid-season?

This was me for the longest time.

I was about ready to give up on growing beautiful planters because I didn't have the time to water twice a day in the heat of the summer (and lets be honest - I didn't want to, even if I DID have the time!) or remember to fertilize weekly, monthly, or whatever schedule I read about and I didn't want to resort to using chemicals.

But then I learned, through trial-and-error as well as exploring solutions, that there are some techniques you can use to grow flowers in containers that really do help your plants look good all season with simple basic care and maintenance.

AND it starts in the beginning, when you're first planting your containers.

If you set the right stage, your plants will have a foundation that will take them through the hot season with much better success.

I'm sharing the exact steps to take, along with a complete tutorial for how to plant containers, that will help avoid the mid-season dried-out-sad-looking containers none of us want to have!

7 Tips for Planting Flower Pots that Thrive

Tip 1: Gather the right supplies

Start with healthy looking plants in complementary colors and three basic "shapes:"

Tall/upright ("thrillers") - example is zinnias in upper left corner in above photo.
Mid-level/spreading ("fillers") - purple & white verbena in upper right corner above.
Trailing ("spillers") - pink & purple calibrachoa & alyssum in lower half of above photo.

You can find more ideas for plant container "recipes" using common nursery-home store plants here: planted container for sun, and here: planted container for shade.

Then grab your supplies to pot up the plants:

Large flower pots - 12" diameter and up, the larger the better since smaller pots dry out faster.
Good potting soil - you can also reuse soil from previous years by amending it - we'll discuss this more below.
Gloves (these are my favorite - inexpensive and easy to garden in) & strong trowel (steer clear of the trowels with a thin neck that attaches the handle to the digging spoon - those always bend in clay soil or when hitting a rock).
Water absorbing crystals - these have been the biggest secret to container success for me! (Note: some people recommend taking apart a diaper to use as water absorbers, but after trying it, I do not recommend it, since my experience after planting was sadly not good and it didn't help hold water as well as the crystals.)
Slow release organic fertilizer. (Not pictured, but a KEY supply.)
Multi-position water sprayer so your tender new plants don't get beat down from the hose's regular spray.
Good quality hose, like the Gilmour Flexogen hose. We went through many cheap hoses that didn't last through a winter before deciding to spend more for one that lasts.

Tip 2: Prep containers & soil

If you're starting with brand new pots, you won't need to worry about refreshing them, but after a year or more of use your pots will look a little worse-for-wear after the winter, like mine pictured above.

Pro Tip (for anyone in climates with frosts): If you don't have the time, space, or inclination to take pots inside (like me), use only lightweight, unbreakable pots. They don't break in the winter, but they do tend to lose their paint after awhile, though that's easy to refresh.

Tips for Planting Organic Flower Pots-container preparation

To get your containers ready for the new season:

Clean the pots well with a spray of water.
Paint pots as needed. To refresh fiberglass/nonbreakable pots each year (or change their color completely) use a basic indoor-outdoor spray paint for whole pots (I find satin is best - flat is a bit harder to clean) and just touch up the rim with a foam brush and regular indoor-outdoor paint as needed.
Trim any plants that overwintered and you want to keep or replant.

Prepare your soil:

Use new potting soil.
OR - Renew old potting soil by dumping it all in a large bin and mixing it with compost. I do this every year and only have to buy new potting soil occasionally - it works great!

Tip 3: Water your plants well before planting

This is actually one of the biggest keys to transplanting flowers - or any plant - that will help guarantee that they will do well:

Make sure the roots are completely soaked using a gentle spray selection on your garden sprayer.

Tip 4: Add slow-release organic fertilizer and water-absorbing crystals to the pots

This is my biggest tip! It literally changed my flower-container-life.

If you do nothing else, after filling your pot 3/4 full of soil make sure to add these two things before planting your flowers:

Choose a slow-release organic fertilizer like this one with a good ratio of nitrogen (promotes green growth) and phosphorus (promotes flowering) - those labeled "all-purpose" are fine. There's a lot more options than there used to be, so many home center nursery departments carry organic options.
Add water-absorbing crystals. You only need about 1/2-1 teaspoon per container (too much and they will absorb so much in wet weather that your plants may pop out!), so a 1-pound container can last years, depending on the number of pots you have.

Doing these two things means you don't have to remember to fertilize if the plants look good and you won't need to water two times a day in the hottest weather.

Tip 5: Space plants according to your planter and massage the roots

Arrange your plants depending on the type of pot.

Pictured above is the plant spacing for a hanging planter that will be seen from all sides: a large, main plant for the center (I love calibrachoa for this - they don't get as gangly as regular petunias) and then 6 smaller trailing/filler plants around the outside (pictured are 3 Creeping Jenny divisions that wintered over, 2 trailing verbena, and 1 alyssum).

Once you have your spacing set, remove the plants and start planting with the center flower.

Remove transplants, massage roots, and plant.

For each plant, gently unpot it by turning upside-down and before setting in place, and massage the roots a bit to break them up.

It's important to break up the roots a bit, especially for any plants that are root-bound, as it helps the roots start to grow into the soil. If you've ever pulled a sad plant out at mid-season to see that the root-ball is the same as when you planted it, you know what I'm talking about.

Plant in the spaces you created, fill in all around the plants with potting soil, and press down well to remove air pockets.

Tips 6: Leave a 1-2" space between the soil and top of the pot and water well

Leaving an inch or so of space will make it much easier to water your pots throughout the season - the water will have a place to gather as it soaks in instead of running immediately off the sides (which will also cause the soil to spill over, making a dirty mess...).

Use your gentle sprayer to water the planted pot thoroughly, which helps to settle the roots in as well.

The photos above are examples of plant spacing for regular pots, using the "thriller (tall plant), filler (medium/full plant), and spiller (trailing)" container formula:

Use 3 plants in 12"-14" pots (one each tall, medium, and trailing), planting as described above.
Use 5-7 plants in larger pots (2 tall, 1-3 medium, 2-3 trailing).

Note: the bottom picture is last year's planters taken in August, to give you an idea of how well the pots do when planted with these tips!

The planting scheme for those pots were: tall thriller = Victoria Salvia, med. filler = geranium & petunia, and trailing spillers = ivy geranium, and mystery pink plant.

Tip 7: Easily maintain your containers

Water every couple of days in cooler weather (check pots for dryness), once a day when it's hot. The crystals make it so you do not have to water twice a day.

Pro Tip: if you live in extremely hot areas, give your pots a once-every-couple-weeks 'kiddie pool soak' - set them in a kiddie pool, fill it with water and let them soak it up for a day (this is also my best vacation watering tip!)

Deadhead (cut off) spent flowers once a week or so.

Pro Tip: if things are looking lanky mid-season for plants like petunias, cut them back - they'll look a bit sad for a week or so, but will bounce back and look better than before.

Fertilize once more mid-season - if needed. Use liquid fish emulsion when watering or apply more slow-release fertilizer on the soil and scratch in a bit before watering well. You'll only need to do this if leaves start to yellow or plants have stopped blooming.

Planting Flower Pots Frequently Asked Questions

When should I plant flower pots?

It depends on your growing season and your last frost. Most annuals we use for containers need to be planted after danger of overnight frosts has passed. Check your last frost date and plan to buy your plants and get them planted in the few weeks after that.
For me in the Western Pacific Northwest, our last frost is around April 15 and I typically wait until the first week of May when there are more plants to choose from at the stores.

Should you put rocks in the bottom of a planter?

I've done that for years for better drainage (as you can see in one of the photos above), but recently read that it's been shown not to be necessary and you can just use all soil. (source)

What can I use to fill the bottom of a large container?

However, if you have a large container (better for keeping the plants moist in the heat), you may want to offset the cost of the soil by filling the bottom with lightweight items like plastic water bottles, crushed soda cans, crushed milk jugs, or plastic take-out containers. Steer clear of foam packing peanuts or containers, as they are very hard to dispose of after the roots have grown into them and they break up into lots of smaller pieces.

What are the easiest flowers to grow in pots?

The list could go on, but these are my favorite, easy to find plants I use over and over:
-Annual Geranium - upright and trailing
-Petunia and smaller Calibrachoa
-Sweet Alyssum
-Verbena
-Chrysanthemum
-Begonia
-Impatiens
-Sedum and Coleus
-Zinnia
-Pansy
-Marigold
-Snapdragon
-Salvia
-Bacopa
-Lobelia

So there you have it - a planting tutorial and my seven tried-and-true tips for planting flower pots organically so they thrive all season!

Do you have any tips to add?

More On Planting Containers

This article has been updated - it was originally published in May of 2015.

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