If you've ever eaten fresh, backyard berries before, you already know that they're far superior to grocery store berries.
And if flavor alone isn't enough reason to grow your own strawberries, consider the health ramifications: conventional strawberries now top the EWG's "Dirty Dozen," and even the organic strawberries in the supermarket might not be what you think--something that became widely reported as far back as 2011.
Bottom line: It's worth it to grow them yourself.
And it's easy too... The plants are low-maintenance and small enough to fit into any garden.. Including hanging baskets!
Today we'll share our tips for growing strawberries in containers, start to finish. In this mega strawberry guide, we'll cover:
- Types of strawberries
- Choosing a container (and which popular option to avoid)
- Choosing the right soil type for strawberries
- How to plant your strawberry plants
- Caring for your strawberry plants
- How to get strawberries to come back next year
- Troubleshooting strawberries
- Companion planting
- Increasing your strawberry harvest
Types of strawberries
Many gardeners, especially those in cold climates, buy new strawberry plants each spring.
What may come as a surprise (unless you're well-versed in strawberry lore): Strawberry plants are actually short-lived perennials, capable of producing fruit for up to three years!
Whether you prefer to treat the plant as an annual or a perennial makes a difference throughout the growing season, but more on that later.
There are four main types of strawberry plants.
June-bearing strawberry plants produce one big crop in May or June. The berries tend to be larger than ever-bearing and day-neutral strawberries. An especially popular variety is the Earliglow.
Day-neutral strawberry plants are less affected by daylight hours and will produce a light, continuous crop all season until the cold kills them. Try the Elan for flavorful medium-sized berries.
Alpine strawberries (also called wild strawberries) continuously produce half-inch sized berries throughout the season. They originate from Europe, where they are still considered a delicacy. Try either the Alexandria Strawberry or the Yellow Wonder Wild Strawberry for some of the most intensely-flavored berries you can grow.
Pro-tip: Some gardeners prefer to keep at least two varieties of strawberry plant: one June-bearing for the large, luscious berries, and an ever-bearing or day-neutral plant for continuous crops all summer.
Choosing a Container
Most containers work well for growing strawberry plants, as long as they are at least 8 inches deep.
- Grow bags
- Self-watering containers
- Plastic pots
- Wire baskets lined with shade cloth or moss..
Hanging baskets should have a diameter of at least 12 inches to accommodate a strawberry plant’s maximum size.
There are many online guides for creative DIY strawberry planters using up-cycled materials. Some of our favorites include the tube planter featured on Urban Green Space blog and this pallet planter.
Keep in mind that if you're treating your plants as perennials, you'll need to move the containers into a garage or sheltered area come winter-time. Choosing planters with wheels can save a lot of hassle at the end of the season.
The One Container to Avoid...
That's right: so-called "strawberry pots" themselves.
Many container gardeners opt for these cute terracotta pots with the individual pockets protruding along the sides.
Despite being sold specifically for strawberries, these pots are more about the form than the function, and are one of the few options that are not ideal for growing strawberries.
The terracotta material pulls moisture from the soil, making it very easy for the strawberry plants roots to dry out (meaning no strawberries for you!).
Many gardeners have complained that the design of the pot makes it difficult to water each plant properly, further complicating adequate watering--all equally bad news for your berry crop.
Not sure what to use for your strawberry garden?
The Micro Gardener has a great chart detailing the pros and cons of many popular options.
Choosing the right soil type for strawberries
Strawberries prefer soil that is slightly acidic. If you’re looking for a ready-made, organic option, our Acid Planting Mix will ensure that you have the right pH for a great crop.
If you prefer the DIY route, you can lower the pH of your regular potting soil by adding coffee grinds or pine needles. Always use a soil testing kit to monitor the soil if you are going to alter the pH levels yourself, otherwise you risk overdoing it and harming your plants.
How to plant strawberry plants
Now that we've got your container and your soil picked out, let's get planting.
If you are growing from seed, you’ll want to start indoors very early in the year; the germination time is long. At this point in the season (mid-April), you’ll want to buy seedlings, so that you can still get a crop off of them.
Just remember to harden your seedlings off before moving them outside for good, after the last frost.
On to the actual planting...
Planting your seedlings is easy-peasy, just...
Fill your container with potting soil and dig a hole wide enough to accommodate your plants roots and deep enough to reach just below the first leaves (the crown).
Pack soil gently around the roots, ensuring they are covered.
Make sure the crown itself is left uncovered, or else it may rot, ruining your plant.
- Give them some water (avoiding your leaves) to get them off to a strong start.
Caring for your strawberry plants
Place the container in a bright, sunny location. It is important not to over water
strawberry plants; doing so can cause gray mold to form. Water plants whenever the top inch of soil becomes dry.
Once the berries are growing, begin fertilizing every two weeks. We recommend using our all natural Bone Meal fertilizer.
Prevent berries from touching the ground by tying the stems onto small wire hoops or by placing straw or plastic sheeting on the ground.
Want them to come back next year?
If you choose to keep your strawberry plants for the next season, they must be overwintered. At the end of the growing season, bring them into a cool, sheltered area such as a garage, basement, or cool room in the house.
Do not keep them in a warm room.
Strawberry plants are temperate and must be exposed to a cold period in order to flower in the spring.
The ideal temperature is 32º Fahrenheit. The plants can survive several degrees below freezing, but the roots of a container plant will die at 25º Fahrenheit.
This is because roots in a container plant aren't as well protected from the cold as roots buried underground.
You’ll want to fertilize them once before winter, and continue to water monthly with a handful of snow or a cup of water.
Harvesting your crop
This is the easy part: You’ll know when it’s time to start harvesting berries! Unless you’re growing the Yellow Wonders, harvest when the berries have turned completely red.
They’ll be easy to remove from the plant by gently twisting them off the stem.
Troubleshooting: Defending your berries against common pests
Plant diseases are uncommon when growing strawberries in containers with fresh potting soil. However, there are a few other problems to look out for… Most of the critter variety!
Slugs: Slugs are just one of the garden critters who agree that strawberries are the best!
Slugs can be deterred by watering the garden in the morning instead of in the evening, and by wrapping copper strips around the base of the container.
You can also fill small cups with beer and bury them halfway into the soil, if your container is big enough. The slugs will be attracted to the beer, fall into the cups and drown.
Birds: Prevent birds from snatching up your strawberries by wrapping the plant with bird netting.
Squirrels: These critters are the bane of gardeners everywhere. They love strawberries and will easily devour a fresh crop.
If they are a problem in your area, try surrounding the container with chicken wire.
Strawberry Root Weevil: A blackish-brown insect resembling a beetle, the adult strawberry root weevil eats leaves and then lays its eggs in the soil. Signs of infection include leaves with bite marks.
Since the weevils feed at night, these marks will appear in the morning. When the eggs hatch, the larvae destroy the plant by eating the roots and crowns.
Organic pest control methods include catching the adults at night and shaking them off the plant, purchasing parasitic nematodes which will eat the weevils, and companion planting.
In most cases, a combination method will work best.
Gray Mold: This fungus may appear near harvest time during rainy and cloudy weather, if the plants are overwatered, or when the berries are touching the ground. The berries will develop soft spots and a powdery gray mold.
If you see any signs of mold, remove the infected berries immediately as it spreads quickly via contact.
Luckily, prevention is fairly simple: Be careful not to overwater your plants, and keep an eye on your berries, staking the stems if necessary, to keep them off the ground.
Companion planting for strawberries
Consider adding a companion plant to your strawberry container. Borage is a particularly ideal companion for strawberries. One particularly useful quality of borage is that it attracts predatory insects, like praying mantis, that eat pests like the root weevil.
It also attracts pollinating insects and is thought to improve the flavour of the berries.
Borage does tend to grow quickly and overcrowd other plants, so it must be pruned regularly when used as a companion plant.
Just remember: members of the cabbage family such as kale or collard greens, don’t do well next to strawberries, so pay particular attention to keep them in separate containers.
Pollinating to increase your strawberry harvest
Heavy pollination can improve crop yields. Though it is not necessary to pollinate strawberry flowers by hand – insects and strong winds usually do the trick – doing so can increase the chance of a high crop yield.
And in case we didn't extoll the benefits of companion planting with borage about, here it is one more time... Companion planting with borage is a HUGE help to your strawberries, including attracting pollinators to your berry patch.
Pollinating strawberries by hand
To pollinate by hand: Simply use your finger or a small brush to rub the pollen from the stamens of one flower onto the pistils (the centre) of the same flower. See step by step photos here.
Special tips for overwintered plants
If you are overwintering your strawberry plants, there's a trick for increasing the next year's crop.
For June bearing plants, pinch all the flowers. You will not get a crop this year unless you buy two plants, one for fruiting and one for pruning.
Pinching the flowers allows the plant to focus its attention on root growth, making for a larger plant the following season.
For ever-bearing and day-neutrals, pinch off all flowers until July. Allow berries to form after that. Year one will have a lower yield, but it can be worth it in the long-run.
Time to get growing!
Strawberry plants are not just easy and fun to grow, they also make for a beautiful edition to any small garden.
With the number of heirloom seeds and ready-to-ship heirloom plants available online as well as the new varieties popping up each year, you’ll have plenty of berries to keep you busy taste-testing season after season.
Need more information about Strawberries? Consult this article from iGardenPlanting.