A heat wave gripped the Northern Hemisphere last week, smashing record temperatures across the United States, Canada, Europe, and the Middle East. I live just outside of Montreal, Canada, a city that hasn’t seen seven consecutive days of temperatures of 87°F (31°C) or higher in over 70 years. While I love floating in the lake on hot summer days, I have to admit I was a little too toasty last week, and unfortunately, so was the spinach growing in my vegetable garden.
Spinach Bolting
About midway through the heat wave, I noticed my spinach had started bolting. Too much heat or sun, and too little water are never good things for this leafy green. In fact, spinach grows best in cooler temperatures; anywhere between 35°F-75°F is ideal.
In extreme heat, spinach responds by forming flowers and seeds. You’ll know your spinach has bolted if it has suddenly grown much taller and its leaves have changed in shape from oval to arrowhead form. Bolting renders spinach quite bitter, and therefore, inedible. I was in denial that my spinach crop was lost and decided to cook it up and put it into a quiche for dinner. “Inedible” is a strong word, but yes, my quiche was seriously bitter. It’s such a shame to see all of your time and effort caring for spinach seedlings go down the drain so soon.
What You Can Do About It
There are a couple of things you can do after bolting occurs (besides putting it into a quiche!). You can pinch off the flower buds that have formed to try to slow the process, although this isn’t usually very successful.
You could also allow it to flower and collect the seeds for next season. Still, there’s no guarantee those seeds will be viable in a year.
Or, you could pull the spinach crops up and plant a new one in its place. Because I’m a keener and so desperate to succeed at growing my own, I’m going with option #3. Luckily I have my gardening bible to help me along the way; Gardening Complete: How to Best Grow Vegetables, Flowers, and Other Outdoor Plants is guiding me through this difficult time.
Succession Planting
Succession planting involves replacing a crop with a new one immediately after the first one has been harvested. With this method, you can easily extend your harvest season with plants like lettuce, spinach, snap peas, green onions, beets, carrots, and other vegetables that mature quickly. Throughout the spring and summer months, swiss chard, kale, and beet greens can be planted in succession every few weeks. This way, you’ll always have a healthy supply of young leaves.
You can also go the route of beginning your summer with a warm weather crop, such as tomatoes and peppers, and after harvest use the same soil to grow a cool-season vegetable, such as lettuce and cabbage.
Before You Start
Before planting a second crop, you absolutely must turn over your soil and add some compost or fertilizer to replace the nutrients used by the previous residents. Leftover roots and other debris from the first crop can cause problems with seed germination, so be sure to clean the soil well.
Know Your Zone
I have to be very cautious about what I plant in my vegetable beds right now; I’m starting from seed, and I live in an area where the growing season is very short. When going ahead with succession planting, it’s very important to be aware of your region’s frost dates. You want to be sure that you plant your new seeds well in advance of very cold temperatures so they don’t die before reaching maturity.
Since I have an abundance of spinach seeds left, and more than six to eight weeks before the first frost in the fall, I decided to go back to the plant that bit me. Wish me luck!