There’s much to do in the garden before we get those May flowers! This time we’re focusing on keeping seedlings healthy and transitioning them to the outdoors, with a few fun facts about May Day.
For most of us in the northeast, our last frost is sometime in May. Four to six weeks before the last frost is an extremely busy time for starting seeds for annuals. Six weeks ahead is a good time for basil and calendula. Four weeks out is a good time for cleome and marigolds. Zinnias and cosmos can be started ahead of time, but do very well if they are direct sown after frost. Sunflowers don’t like being transplanted, so wait to plant them until it’s warm.
How are your seedlings doing?
If they’re tall and spindly, with weak, skinny stems and small leaves, they’re “leggy”: they need more light. The light source should be about two inches from the plants. Seedlings that are too warm can also grow taller and thinner than they should.
How are your seedlings doing?
If they’re tall and spindly, with weak, skinny stems and small leaves, they’re “leggy”: they need more light. The light source should be about two inches from the plants. Seedlings that are too warm can also grow taller and thinner than they should.
If your seedlings are turning yellow, they may be overwatered or may just be hungry! Once they have some true leaves (the first leaves are “seed leaves”), you can begin to fertilize them. Keep in mind, if your seed starting mix contains slow release fertilizer, you may not need to feed your seedlings at all! If you’d like to, make sure to use a formula specifically for seedlings or dilute your standard fertilizer. Many labels have guidance for the concentration to use for seedlings; if not, use ¼ strength. Using anything too strong can “burn” your plants and will harm them. If the tips of leaves turn brown, it may be a sign of too much fertilizer. It’s better to feed a lesser amount at regular intervals than to use high amounts sporadically.
While your seedlings get established indoors, they’ll need good air circulation. Turning on a fan will help with this and can also help strengthen them so they can stand up to mother nature’s breezes. Good airflow can prevent “damping off” – when seedlings look fine, then suddenly wither and flop over. This is caused by a fungus or mold that causes roots and stems to rot and is most common in cool, wet conditions. Planning ahead, making sure that your tools, pots, and trays are sterilized (10% bleach solution) and your soil is new and clean can help prevent damping off.
As they get bigger, they may benefit from being allowed to dry slightly between waterings. This can prepare them for dry days between rain showers or drinks from the garden hose. Just don’t let them dry out completely.
Hardening Off
As the weather warms, the time to plant seedlings outdoors will be approaching (finally!). It’s important to take the time to gradually transition them from indoor conditions to outdoor conditions. They need to acclimate to “real” sun, wind, and temperature swings. This process is called “hardening off.”
Start by putting your seedlings in dappled shade for just a couple of hours. Gradually add a few more hours each day, giving them a little more sun each time. There’s a lot of moving back and forth between sun and shade, inside and outside, with less and less protection until they are ready to fend for themselves. Don’t rush it, though! Going straight into the sun can lead to scalding (leaves looking bleached and dry), and staying out in the cold without a transition can cause shock from temperature swings.
If you’re well into hardening off and plan to have seedlings outdoors overnight, but there’s a risk of it getting too cold, you can create a makeshift greenhouse. I’ve done this in a pinch with a heavyweight plastic painter’s dropcloth (just a few dollars at the home improvement store) tented over some bamboo stakes. I clip it in place, and – voila! – a cozy tent for the night. You can also purchase frost cloth for the same purpose; some options come on frames that you can extend out like a caterpillar. Just be careful with any plants that really need warm temperatures – tomatoes, peppers, eggplant, basil prefer 50° or warmer at night – and make sure they are safely indoors if there’s any risk of cold.
If you’re well into hardening off and plan to have seedlings outdoors overnight, but there’s a risk of it getting too cold, you can create a makeshift greenhouse. I’ve done this in a pinch with a heavyweight plastic painter’s dropcloth (just a few dollars at the home improvement store) tented over some bamboo stakes. I clip it in place, and – voila! – a cozy tent for the night. You can also purchase frost cloth for the same purpose; some options come on frames that you can extend out like a caterpillar. Just be careful with any plants that really need warm temperatures – tomatoes, peppers, eggplant, basil prefer 50° or warmer at night – and make sure they are safely indoors if there’s any risk of cold.
May Day!!
The end of April and beginning of May, when trees are blossoming, pollinators return, and baby animals start appearing, really feel like spring.
May Eve (April 30) and May Day (May 1), have long been accompanied by celebration. In ancient Rome, a week was given to the celebration of the goddess Flora, a goddess of flowers — especially the blossoms of fruit trees. In Germany and Scandinavia May Eve came to be part of a Christian feast, for Saint Walpurga (Walpurgisnacht in German). May Day was called Beltane among the Celts. Celebrations included bonfires, feasts, singing and dancing, and, of course, the May pole with its ribbons. Learn more here.
However you embrace the arrival of spring, it won’t be long before you’re sitting in the sunshine admiring how much your garden has grown.
