The most wonderful time of the year: Spring blossoms are about to make their debut, signaling the beginning of growing season.
It’s cathartic and thrilling to buy new plants and gardening supplies for your space's annual spring fling. However, many of us jump the gun and end up with sad—or worse, DOA—seedlings and unrealized veggies that never saw their big day on the grill. To time things just right, we spoke with gardening expert and landscaper Kara Kolodziej-Matsueda, owner of Bittersweet Gardens NYC.
What are three things we should be doing to prep our gardens and patio planters in March and April?
A thorough spring cleaning is always a great place to start. For planting beds, remove (recycle or compost) any debris, including leaves and fallen branches. A few leaves here and there are good for soil composition, so you don’t have to go crazy! As a general rule, it’s best to remove any dead, damaged, or diseased limbs, stems, and branches from trees, shrubs, and perennial plants. You can go by this rule any time of year. Last but not least, apply slow-release fertilizer to trees, shrubs, and perennials.
For container plants, do a visual inspection of all containers. Replace pot feet. Drainage is absolutely necessary for healthy container gardening. I cannot stress this enough! Evaluate the soil: How long have you been using the same soil in the same container? With watering, soil nutrients can leach out from drainage holes at the bottom of the container.
For both beds and containers, you should add any special fertilizers to roses, evergreens, and shrubs. Late March is a good time to prune trees, as they are still in their dormancy. This is also when you should spray horticultural oil on any plant life that is prone to be host to overwintering pests, such as mites or sap-sucking aphids.
What do we need to know about the transition from winter to spring for our perennials as well as our soil?
A lot of tree pruning should occur during the winter months while trees are dormant. With dormant pruning, the tree’s only job is to heal the wound made by the cut. In warmer weather, pruning will stimulate new growth, which further taxes the energy reserve of the tree. A healthy tree may survive the extra stress, but a weaker one may not. Rule of thumb is to prune no more than a third of the tree’s canopy in a season.
You will also want to add some type of general slow-release granular fertilizer to the plants in your garden bed to help them grow strong for the season. If you garden organically, mixing in some compost with the soil while planting or adding a one-inch layer to top-dress the soil will also do the trick.
If your perennials have outgrown their space, spring is the time to divide (and conquer) for plants like daylilies, hostas, and garden phlox.
Why do seedlings always seem to die before we can get them in the ground? Is there a secret?
I think the biggest problem we have with seedlings is spring fever. Most people seed too early. The seedlings are stuck trying to thrive in the tiniest of containers with roots that often outgrow their pots before we can get them outside.
The secret? A good rule of thumb is to start seedlings inside six weeks before the last frost. Which, in New York City, can be as late as the second week in April. The Old Farmers’ Almanac can provide you with a planting calendar according to the local last freeze date.
If we want to grow container vegetables, what do we need to get started?
Growing container vegetables is relatively easy if you have a nice sunny area and easy access to an outdoor water supply. I would say give tomatoes (actually a fruit!) at least a foot and a half of soil depth to grow. Some people use a five-gallon bucket with holes drilled into the bottom for drainage. Root vegetables need a greater depth, as they develop under the soil surface. I would say 24 inches of soil depth is a safe bet for any vegetable.
What is the No. 1 mistake most home gardeners make in the spring?
That’s a hard question. I’d say improper pruning can have myriad effects. It can stunt the growth of the plant, destroy its natural form, and eventually lead to the weakening of the plant physiology, which translates into being an easy target for disease and pests.
What are the best decorative plants if you're having a lot of outdoor parties?
Grasses create movement in a garden and are available more for sunny spots than shade, but there are some shadier options like Chasmanthium latifolia, Northern Sea Oats, some Carex, and varieties of Liriope that will do well in shady conditions.
I would choose a mix of annuals and perennials. Annuals are bred to bring vibrant, lasting summer color to your garden, whereas perennials usually have a short bloom season. I use perennial containers as a framework for the garden space and annuals to fill in the gaps. It’s easy to switch out annuals to celebrate the current season. Spring daffodils can be easily pulled out and replaced with geraniums for the summer months, and then replaced with decorative kale or chrysanthemums for the fall.
If you have a lot of shade in your garden, there isn’t a huge variety of colorful plants to choose from. I usually concentrate on texture and form, using different colors of green foliage to create contrast. For example, different varieties of hostas combined with different ferns can create an interesting shade garden with varied heights and colors.
The golden rule for gardeners is “Right plant, right place.” (Meaning, read the tag of the plant you are interested in.) A plant that likes shade to part shade will absolutely not thrive if planted in a spot that is sun/part sun. It will probably end up looking a bit droopy with some scorch marks from too much sun.
The Missouri Botanical Garden is a fantastic resource for all levels of gardeners. They have guides for tropicals, perennials, vegetables, trees, shrubs, and everything in between. They have plant lists by common and scientific names, as well as specifications for growing each plant.
If you're a big griller, is that bad for your plants? Should we place the grill away from our container pots, for example?
Argh, keep that grill away from your containers! The radiant heat from the grill will be sure to literally cook your beautiful greenery.
Summers seem to be getting hotter around the country. What's the best, most efficient summer watering system for gardens?
The best watering system is, without a doubt, an automated irrigation system. Even with the best of intentions of caring for your plant babies, it can end up being A LOT of work, especially in July and August when the weather is warmest. Plants that are weakened by lack of water and nutrients (fertilizer) end up being more susceptible to disease and garden pests. Who wants to spend their summer nursing plants back to health when they should be performing at their peak?
There are smart irrigation systems available that you are able to control with an app. You can change watering frequency with the weather. Heat wave? Crank it up a notch. Raining for three days? Maybe turn the system off until the sun comes out again.
What's the easiest way to move indoor plants outside for summer?
When moving plants, it’s important to slowly introduce them into their new environment. When the weather is above 60 degrees Fahrenheit during the day, most tropical plants can be moved outside for a few hours and brought back inside for the night. Gradually increase the time, until night temps are 55 degrees F and above.