One of the most delightful parts of gardening is realizing that a garden can be anywhere. Bright and beautiful gardens can thrive on tiny balconies, patios and even windowsills with carefully selected plants and containers. Container gardening not only gives the gardener opportunity to grow in small spaces, but also to be selective about soil, sunlight and moisture. With the right combination, anyone can enjoy a bountiful container garden!
The first step is the container. A good rule of thumb for choosing the right container is to imagine the mature size of your plant, and mirror that with your container. So, a pepper that reaches eighteen inches tall at maturity will need a container that is at least eighteen inches deep. Whenever possible, bigger is better! Larger pots allow for larger, more robust root systems and require less frequent watering.
Container material is another important consideration. Natural materials like terra cotta and wood are porous, meaning water can wick away through the walls of the pot. While this is a benefit in wet areas where oversaturation can lead to fungal disease, in dry climates it may mean your pots dry out too quickly. Glazed clay prevents water loss, making it a good alternative for dry land gardeners. Plastic, too, is non-porous and lightweight but can be quick to deteriorate. Look for high quality, durable plastic. Whatever the material, the most important part of any pot is drainage – always make sure there are holes at the bottom of your container.
Once you’ve selected your container, you’ll want to fill it with a good quality potting mix. The best mixes are both free draining and moisture retentive with ingredients like shredded forest products, perlite and coconut coir. Please avoid any mix containing peat. This valuable resource is being harvested at non-renewable rates, releasing tremendous amounts of stored carbon into the atmosphere and damaging critical wildlife habitat. As English gardener and sartorial hero Monty Don has said: “Extracting peat is every bit as damaging to the climate as cutting down the rain forest but much harder to renew. It is an ecological and environmental disaster.”
Fortunately, coir is a good alternative and becoming more widely available. Compost, whether homemade or purchased, will aid moisture retention and bring your soil mix to life with all those helpful microorganisms. Plants in the ground develop complex, symbiotic relationships with the soil microbiome – relationships we can help imitate in containers with the addition of compost.
Some soil mixes will come with composted chicken manure or worm castings. These will act as a slow release fertilizer as they decompose and make nutrients available to the plant roots. If you’re considering growing heavy feeders like tomatoes or peppers, you may want to add small amounts of organic fertilizer, either one application of slow release fertilizer at planting – like fish meal or cottonseed meal – or regular applications of liquid fertilizer – like fish emulsion.
Before planting, moisten your soil mix and incorporate any added compost or granular fertilizers. Ultimately, you’ll want the base of your plants to be about one inch lower than the rim of your container so add soil accordingly. Planting too high makes it challenging to water; too low and you sacrifice all that extra root growing space. Once you have your plants or seeds in the soil, water thoroughly until you see water draining through the holes at the bottom of your pot.
Careful watering is key to a successful container garden, since plants in pots are unable to access deeper water reserves the way plants in the ground are. In general, you want to water whenever the top inch of soil dries out. While there are lots of fancy meters and gadgets that will tell you when to water, the best tool for the job is your finger. Push your finger into the soil just past your first knuckle and if it feels dry, time to water! Always water until it begins to drain out of the bottom of the pot to ensure the soil is saturated.
Once you start spending more time with your plants, you’ll begin to read their cues. Though it may sound woo-woo, plants are always communicating with us, letting us know when they need more or less water, more sunlight or a splash of fertilizer. We like hand watering for this reason as it provides one on one time with your garden. But choose whatever method of watering you can maintain consistently, whether that’s a drip irrigation, a self-watering pot or a good old-fashioned watering can.
Lastly, it’s important to consider sun exposure. Most vegetables require at least six hours of sunlight during the growing season, and many flowers bloom best in full sun. If sunlight is variable in your space, try placing your containers on wheels and moving them to sunny spots throughout the day. Or, give some of the more shade tolerant plants a try. Leafy greens like lettuce and spinach can tolerate as little as three hours of sunlight, as can shade tolerant impatiens and coleus.
Now that we’ve covered the nuts and bolts of container gardening, it’s time for the fun part: picking the plants! There are many varieties of herbs, veggies and flowers that do well in pots and the selection can seem daunting. To narrow down the choices, consider which plants you enjoy most, or which will be most useful in the kitchen. Coming up with a theme helps group plants with similar needs together, and gives your container garden a cohesive look.
Herbs make wonderful container plants, being both beautiful and useful. Try growing a Mediterranean themed herb garden with large clay pots of lavender and rosemary under-planted with trailing stems of oregano or flowering thyme. These plants are sun lovers and can withstand dry spells better than others, perfect for your sunniest spots. Lavender is an exceptionally well suited container plant, adaptable to lean or fertile soils and wet or dry conditions. Plant lavender in a compost rich soil with chamomile, mint or lemon balm for a sweet-scented “tea pot”! Mint and lemon balm are often better behaved in containers than in the ground, where they have a tendency to take over.
All of your container herbs will benefit from regular harvesting to keep them compact and productive through the season. Annual basils will last longer if you pinch off the upper leaves regularly to prevent flowering. Try growing a pesto pot with several different varieties of basil, or our organic Culinary basil blend to make rich and zesty pesto all summer long. If you’re short on harvesting time, recruit your house cat! Cat grass does beautifully in containers and your cat will do all the grunt work come harvest time.
If, alternatively, you delight in harvesting home grown produce but are faced with limited sunlight, plant an assortment of salad pots. All of our leaf lettuce varieties are good candidates for container gardening. Look for our mesclun zesty salad mix, salad blend, and both our salad bowl red and green mixes. Even head lettuces can be grown as cutting greens if you harvest the young leaves often.
To create a cut and come again salad pot, sprinkle your chosen seed mix densely over the soil surface. Cover lightly with soil, pressing down gently to ensure good contact, then water well. Salad greens are fast growing and should reach a few inches tall within a few weeks. Look closely at the center of each plant and you’ll see the point where the tiny new salad leaves begin to unfurl. This is the point you want to cut above when harvesting. Take a big handful and snip right above that growing point. The little leftover stumps will quickly shoot up new growth for you to repeat the process, enjoying many homegrown salads!
Lettuce is not the only successful container candidate. Arugula, spinach, mustard greens, kale and even Swiss chard can grow well in containers. Try planting Lacinato kale seedlings in the center of a generous pot, then sprinkle thickly with arugula seeds. As you harvest the lower leaves of kale, the arugula will steadily fill in the available space making for a very dramatic and beautiful pot.
Some of our veggie varieties were developed specifically for small space growing. Spacemaster cucumbers grow on compact two foot vines, making them ideal for containers. To keep the fruit from resting on the ground, insert a sturdy trellis on one side of your pot, and train the vines to grow up it. Low growing Finger Fruit eggplants bear 4-6” fruits on beautiful purple-tinged plants. Let the fruits spill over the rim of a colorfully glazed pot for a lovely effect.
Even the most coveted summer vegetable can be grown in containers. The Tumbler tomato produces abundant clusters of cherry sized tomatoes on petite two-foot-wide plants. This bush plant is considered determinate, meaning it grows to a fixed size, unlike indeterminate vines that grow continuously. All tomatoes have vigorous root systems, so pick an extra-large pot and fill with a rich blend of soil and compost.
No discussion of container gardening would be complete without mention of the humble flower pot. In our opinion, all flowers look good in a pot, from the ubiquitous geranium to the towering sunflower. There is a pot for every flower. But there are a few ways to elevate your flower display. Perhaps you’ve heard of the design mantra: thriller, filler, spiller? This catchy phrase is a useful way to lay out your flower display.
Thriller flowers are often planted at the center or rear of the container. These are your real showstopper plants, with long stems and eye-catching blooms, they are the focal point of your display. Blazing star with its vibrant purple flower spikes held on three to four foot stems, or Sunspot dwarf sunflower with full size flowers on two foot stems are excellent thriller plants. Other options include: castor bean, coleus (for partial shade), cosmos, foxglove, larkspur, Showy milkweed and zinnias.
Filler plants do exactly as you’d expect: they fill in the pot, hiding any bare stems of the thrillers and providing a gentle resting point for the eyes. Popular filler plants are any of the violas with their long blooming season and modest height, or marigolds for a shock of color atop bushy green leaves. Other fillers are calendula, Aspen daisy (fleabane), dianthus, and any of the pansies.
Last but not least, spiller plants spill over the edge of the pot completing the look and giving a dramatic flair. Plant creeping baby’s breath or creeping thyme close to the edge of your container and let the flowering stems hang gently over the edge. lobelia’s velvet purple flowers look lovely spilling over a terra cotta pot, or plant snow in summer for a cascade of white blooms.
However you design your container garden, whether with vibrant flowers, tasty vegetables or herbs, you can feel good about giving a bit of our built environment back to the garden. Every garden matters, even the very smallest!