Q: I seem to have trouble keeping my herbs alive. Do you have any tips to help them thrive even late in the season?
The majority of the culinary herbs we grow—oregano, lavender, sage, and rosemary to name a few—are Mediterranean in origin. As a result, these herbs tend to be associated with everything summer: long, hot days, sweltering nights and plenty of sunshine. But even the most tenacious, drought-tolerant herbs have their limit.
Sometimes we expect too much of them; an unreasonable endurance through scorching heat waves, extended periods of drought and weekends away where they are left to hold their own. It’s tough out there! Fortunately there are simple strategies that you can employ to help your plants deal with mid- and late season extremes. Try these:
Thin the Herd
Don’t be afraid to remove a plant or two if a pot is overcrowded. This is a really common ailment with mixed herb containers and window boxes. Gardeners tend to cram too much into pots in the spring when the plants are small and cooperative. By summer they turn into beasts, competing for root space, nutrition and moisture. Quarantine that thuggish peppermint to its own pot. Even parsley tends to be happier on its own.
The Heat is On
Excessive heat is probably the main source of mid-season herb stress. Potted plants are even more likely to suffer the effects of heat and drought than those in the ground or a raised bed. Fortunately, they come with the convenience of mobility. Move plants that are showing signs of distress or pots that dry out too quickly into a protected spot underneath a gazebo or into the shadow cast by your home, shed or a tall fence.
Check your soil’s moisture daily. Poke your finger in at least an inch deep. It’s not uncommon for the soil to become drier than you think, and once it does it could take a few generous applications of water to rehydrate.
Note that a pot that dries out constantly is a tell-tale sign that your plants need an upgrade; either to a bigger pot that can accommodate their growing roots or a plastic container with better moisture retention. Parsley, chervil, lemongrass, mint, violets and sorrel are happiest in deep pots with consistent moisture.
Basil may be known as a sun-loving plant, but it doesn’t always hold up against the harsh rays of the noonday sun, especially once the true summer heat kicks into overdrive. Plant basil alongside and underneath indeterminate (vining) tomato plants. They may be the same size at planting time, but come summer the tomatoes will be tall and leafy, stepping in to act as a living, protective parasol just when the basil needs it most. Cilantro, arugula, nasturtiums and spreading thyme varieties can benefit from this arrangement too.
The Midsummer Chop
Many perennial herbs such as mint, oregano, catnip and marjoram start to look burned out, scraggly and weather beaten around midsummer, especially after a big flush of flowers. Give these plants a rejuvenating haircut shortly before or after they finish blooming – you’ll be surprised by how quickly they bounce back with a new crop of healthy leaves, sometimes better and bushier than before. Don’t be timid; chop them back by half and wait for the new, greener growth to emerge.
Garden authority Gayla Trail is the creator of YouGrowGirl.com.