By Dave Zeldon and Ely Schweyer
Starting the first week of January, seed packets of many vegetable garden delicacies began arriving at your local garden centres. It’s a great time to plan your gardens and purchase your seeds while the selection is good but don't sow your seeds too early!
If started too soon, your plants will be leggy and overgrown long before you can transplant them into the garden. The general rule of thumb (even if yours isn't green), is if the seed packet recommends sowing four to six weeks before the last frost date, it's better to pick the four - rather than the six-week date (to calculate the sowing date, count back from the third week of May).
In this blog post, we’ll discuss the proper timing of the beneficial companion planting practice, to ensure an organic triple-play of pesticide reduction, nutrient sharing, and the fruits of your labour actually tasting better!
What is Companion Planting?
The use of companion plants is an organic approach embracing plant diversity that involves growing certain different types of plants near each other. By mixing a variety of plants together you confuse harmful insects (i.e., the ‘Three Sisters,’ corn, beans, and squash). When you plant certain vegetables together or alongside flowers or herbs, you can often camouflage the scent of a given plant so that its potential enemies can't find it. For example, if you plant onions and carrots together, the Carrot Rust Fly can no longer detect the scent of its "prey," the carrot.
☝️ Plants also share nutrients and amend the soil below ground – in the instance of the Three Sisters, beans fix the nitrogen content of the soil for corn, who has long lost its ability to produce its own nitrogen.
What to Plant?
Herbs Make Excellent Companion Plants
Instead of grouping them all together in a corner, plant them in among your vegetables. Tarragon and marjoram give off a scent that repels most insects. Sage, rosemary, and thyme repel insects that feed on the different plants of the cabbage family. Plant these herbs near your cabbage, cauliflower, and brussels sprouts. Coriander attracts parasitic wasps that are very useful in controlling all sorts of pests.
🖱️ See more on companion planting with herbs here.
Why Not Try Flowers in the Vegetable Patch?
Nothing will make your vegetables happier! Plant borders of alyssum and cosmos; these attract beneficial insects and repel certain harmful ones. Marigolds protect tomatoes from threadworms, and nasturtiums and petunias attract aphids. If you plant them near your tomatoes, the aphids will choose the flowers instead of your tomatoes.
Meet My Plant Friends!
Plant friends are plants that can be grouped together because they mutually help each other grow. Basil stimulates the growth of Tomatoes and enhances the quality of the yield. Chamomile improves the growth and taste of cabbage and onions. It has been found that peas and beans enhance the growth of cucumbers and potatoes. Peas and beans also repel the Colorado Potato Beetle that commonly attacks potatoes and eggplant.
Once you’ve decided who is going where, it’s time to focus on when who is going where.
When To Plant?
It is important to know when the last spring frost date is for your area. Many plants need to be planted after the last frost, so that they don't freeze their little buds off! Follow this guide so that you can have healthy, sturdy little plants that will become good friends in your garden this summer.
| Ten Weeks Before Last Frost Sow indoors: broccoli, brussels sprouts, cabbage, cauliflower, eggplant, lettuce, peppers, and onion |
| Eight Weeks Before Last Frost Sow indoors: tomatoes Sow outdoors: spinach |
| Five Weeks Before Last Frost Sow indoors: marigolds (do not transplant until after last frost) Sow outdoors: peas Transplant: broccoli, cabbage, cauliflower, onion |
| Four Weeks Before Last Frost Sow indoors: cantaloupe, cucumbers, okra, pumpkins, squash, and watermelon |
| Three Weeks Before Last Frost Sow outdoors: carrots Transplant: brussels sprouts, hardened off frost-hardy herbs like chives and oregano |
| Week of Last Frost Sow outdoors: pole beans Transplant: cantaloupe, eggplant, lettuce, okra, peppers, pumpkins, squash, tomatoes, and watermelon |
BONUS: Tips on Ensuring Your Seeds Have the Best Start!
🌱 To ensure success it is always best to use fresh, sterile seed-starting mixture (available from garden centres). Moisten mixture about an hour before sowing; it shouldn't be soggy, just as damp as a wrung-out sponge.
🌱 Follow the information contained on seed packets in terms of timing, lighting requirements, sowing depth, and optimal germination and growing temperatures.
🌱 Lightly water freshly sown flats, then cover with plastic dome lid, or if reusing containers try placing them inside a plastic zip-lock bag. At the first signs of germination, uncover or remove from plastic bag.
🌱 As the seedlings develop, wait until the top of the soil looks dry, water carefully using a small watering can with a fine spray. Avoid over watering: soggy soil and poor air circulation can lead to damping off, a fungal disease that can kill seedlings.
🌱 Locate your seeding flat in a bright window but grow lights or cool fluorescent tubes are better. Keep seedlings about eight to 10 centimetres from light source to prevent plants from becoming too spindly. Plug lights into an automatic timer set for 16 hours on, eight hours off. Be careful if you’re using the windowsill method though, as extremes in temperature may occur from hot drying sunny days to frigid evenings.
🌱 When seedlings have two sets of true leaves (the first leaves are called cotyledons — or seed leaves — so wait for the true ones, start feeding once a week with a balanced (20-20-20), water-soluble fertilizer at half-strength, working up to full strength after a few weeks.
🌱 Finally, the plants which have been raised under sheltered conditions must now be hardened off (see more here) before planting out. Gradually lower the temperature and reduce the watering while exposing the plants to brighter light for seven days prior moving them out to a cold frame. Keep an eye on the weather as sudden changes, as it often happens in spring, could spell disaster to your young plants.
We hope your garden is biodiverse and fruitful this year! For more information – and companion plants – visit Eising Greenhouse and Garden Centre this spring! 🌿
What’s the best way to brighten up your garden? Add lots of annual flowers in the Spring! Here in Southern Ontario, the May holiday weekend is usually safe from frost - and go time for planting tender annuals!
At Eising Garden Centre, you’ll find a wide array of beautiful annual blooms. Here are ten of our sun-loving favourites to try.
Cosmos
With daisy-like blooms in radiant shades of pink, red, and pure white adorned with mellow yellow centres—Cosmos are irresistible. They're perfect planted along a fence or at the back of a border, where they can lean on a little support. Depending on the variety, Cosmos can grow anywhere from 12 to 80 inches tall!
Zinnia
Bold, structured, and bursting with colour, Zinnias bring serious wow factor. Their cheerful blooms come in red, green, orange, yellow, purple, pink, and white. Depending on the variety, Zinnias grow between 6 and 36 inches tall and spread about 12 inches wide.
Calendula
Decorative and useful, Calendulas are edible flowers with culinary and medicinal value. Their soothing, antiseptic properties make them popular beyond the garden. Calendula come in gorgeous, bright shades of copper, orange, gold, and yellow blooms and grow 10 to 24 inches tall.
Marigold
Tough and reliable, Marigolds handle heat and humidity with ease, thriving even in the driest parts of your garden. They offer a beautiful range of bloom types—from large, ruffled flowers to small, delicate blossoms—and a palette of cream, yellow, orange, red, and bi-colours. Depending on the variety, Marigolds can grow from 6 to 36 inches tall.
Amaranth
If you're after drama, Amaranth is your plant! Reaching heights of 3 to 5 feet, these bold beauties flaunt long, rope-like clusters of maroon or red flowers. While low-maintenance, Amaranths may need a bit of support to stay upright as they mature.
Portulaca
Perfect for hot, dry, and neglected spots, Portulacas deliver a brilliant show of colour with minimal effort. Their rose-like blooms come in vivid shades of red, pink, yellow, white, orange, and purple. Low-growing at just 4 to 8 inches tall, they're ideal for the front of borders, or alongside driveways, and patios.
Salvia
With tall spikes of bold purple, red, blue, pink, or white blooms, Salvias are garden standouts. Growing 8 to 24 inches tall and often blooming continuously, they quickly become must-haves for flower beds or large containers.
Geranium
Drought-tolerant and tough as nails, Geraniums have long been a gardener’s favourite. Regular deadheading (removing spent blooms) will reward you with non-stop flowers until frost. Their lush foliage and bright flowers—ranging from salmon, white, purple, violet, and orange to red and pink—also shine in mixed containers. Geraniums typically grow between 8 and 24 inches tall.
Petunia
It’s no surprise Petunias have remained beloved for generations. They grow quickly, bloom prolifically, and require little care. Available in mounding or trailing forms—and sometimes carrying a heavenly scent—Petunias are perfect for flower beds, hanging baskets, pots, or window boxes. Growing 6 to 18 inches tall, they come in white, yellow, pink, purple, red, bi-colours, and even black!
Dahlia
Dahlias can become a full-on passion project—and it’s easy to see why. Their breathtaking blooms come in a stunning range of sizes, shapes, and colours. While Dahlias can be a bit particular (they love rich, well-drained soil and plenty of water, but hate soggy conditions), they are absolutely worth the extra attention.
Sunshine + Food + Hydration = Success
All of these annuals thrive in full sun and will reward you with even more blooms when given consistent water and fertilizer.
Adding a continuous-release fertilizer to your soil at planting time—or feeding weekly with a balanced, water-soluble fertilizer—makes it easy to keep your garden thriving all summer long!
*TIP: Check our handy Plant Finder for more details! https://plants.eising.ca/11110015/