The following is from a talk given by Carol Allen at Behnke’s:
Herbs need full sun (meaning horizon to horizon sun). If you’ve had problems with growing herbs in the past, this may be why. Sun not only helps the plants grow well, it also helps their production of essential oils, which is what gives them good flavor. A good indicator of full sun is a good tomato crop; if you’re able to grow a tomato plant that gives you plenty of tomatoes on a nice, bushy plant, you have full sun. If you don’t have full sun, try a community plot.
Because weather will affect your homegrown herbs, it’s important to remember that the flavor won’t be consistent from year to year. Always smell them before use to determine how potent they are. Homegrown herbs are best used immediately after picking and are best picked in the morning (they spent the night turning the previous day’s sun into essential oils and the sun has yet to cause some of those oils and moisture to evaporate). Of course, this isn’t always ideal—who wants to make dinner first thing in the morning?—do what works for you.
When cooking with herbs, remember that strong flavors will cancel each other out and that you will need to use more of a fresh herb than a dried one. Carol gave this equation: ¼ teaspoon dry powered = ¾-1 teaspoon dry crumbled = 2-4 teaspoon fresh. If using dried herbs, make sure they’re not too old because they will lose flavor the longer they sit on your shelves. If they’re more than a year old, throw them out. If you’re making a dish with a long cooking time, like a soup or stew, you may want to add some herbs towards the end of cooking because cooking will reduce their flavor. If however, you’re making a dish that doesn’t require you to cook the herbs (i.e. salad dressing, potato salad, etc.) it will probably benefit from being made ahead of time and allowed to sit overnight so the flavors can meld. The one exception is when using basil; it will get bitter if allowed to sit too long.
Carol’s favorite way to enjoy the full flavor of an herb? Make a compound spread. Her recipe is 1 tablespoon finely chopped fresh herbs to ½ cup butter, cream cheese, cottage cheese or yogurt. Mix together and enjoy at room temperature.
Whether it’s homegrown or store bought, how you store your fresh herbs can greatly improve their shelf-life. For hardy herbs, like rosemary, sage, thyme, savory and chives, wash, dry (a salad spinner works wonders) and roll in a dry paper towel before placing in a ziploc bag in your refrigerator. For tender herbs, like parsley, cilantro, dill, mint and tarragon, wash and dry, then re-cut ends and place in a glass with a little water, cover loosely with a plastic bag, place a rubber band around the bottom to secure the bag to the glass and place in the ‘fridge. And then there’s basil: wash and dry, re-cut the ends, place in a glass with a little water and then leave uncovered on your counter at room temperature.
Make sure your soil drains well. If you’re planting in containers, it’s a good idea to amend your potting mix with 10% by volume of something to facilitate drainage, like perlite/vermiculite, orchid bark, mulch or gravel. If you’re planting your herbs directly in the garden, make sure that when you water (or when it rains), the water doesn’t pool, but sinks quickly into the soil. If you have poor soil drainage, you’ll want to mix your soil with something like wood chips to help create air pockets in the soil.
Also, before planting in your garden, it’s a good idea to do a soil test. You want to know the pH (different herbs like different pH levels), how much organic matter there is (organic matter, like compost, is good, but you can have too much; you want no more than 3%) and nutrient levels so you know what to add for optimum growth.
Carol recommends mulching Mediterranean herbs that prefer drier soil (rosemary, sage, lavender) with pebbles instead of bark. They allow for better air circulation around the base of the plant and will help draw excess moisture out of the soil.
Planting in Containers
Mixing herbs together in containers can be tricky. You want to plant herbs together that have the same needs; for example, it would be a bad idea to plant Mediterranean herbs that don’t like a lot of water with herbs that do. You also need to pay attention to the space requirements of each herb. When you buy a pre-planted herb container garden, it may be beautiful, but chances are that the herbs in it are going to need more space in a couple weeks. Basil and mint should not be planted with other herbs because they will out-compete everything else. In fact, mint can out-compete much larger shrubs if planted directly in the garden, so unless you have a nice, sunny patch with nothing else around, plant it in a container on its own. Keep pots with mint out of contact with the ground, as the mint will grow out of the drainage holes in the bottom of the pot.
A Few Favorite Herbs:
A member of the mint family, it’s native to Iran, India and tropical Asia and has been cultivated for 5,000 years. ‘Genovese’ is a good standard sweet variety, but Carol also likes Thai basil (like ‘Siam Queen’) for extra heat and it’s a must if you like to make Vietnamese pho noodle soup. When planting basil in a container, make sure it has a good size pot, at least 14” in diameter, and don’t mix in other herbs. Give it full sun. When starting from seed, it will take 75-85 days to reach maturity.
If your basil plant starts to look bad in July or August, chances are it probably has a plant disease called downy mildew and that spells the end of the plant. And, because downy mildew lives in the soil, it will affect the next plant you put it in. Don’t reuse the soil and scrub the pot thoroughly before reuse.
A cool-weather plant that may not always stand up to our hot summers, though it can take a light frost in fall if covered. It’s a member of the carrot family and ladybugs love eating pollen from carrot family flowers, so let some go to flower to attract ladybugs. It likes full sun and a soil pH of 6.5-7.5. From seed, it takes 45 days to reach maturity.
Another member of the carrot family, parsley is a food source not only for ladybugs, but also for swallowtail butterfly larvae. It’s a biennial (meaning it lives for two years), so if you plant it every year and allow the plants in their second year to go to flower, you’ll always have some for yourself and some for the butterflies and ladybugs. If however, you would rather keep insects from eating your parsley, you can always use floating row covers to keep them out, just make sure there are no holes in the fabric, because otherwise butterflies will find their way in. Bunnies also have a taste for parsley. To keep them out, create cloches out of chicken wire or plant them within a fence.
If growing from seed, you’ll want to start them early, like January, because they can take up to 6 weeks to germinate. They can take part shade and are frost tolerant; just mulch them up to their eyebrows in straw when it gets colder and you’ll be able to harvest even in winter.
Perennial! They can live a long time (Carol’s had the same chives in a pot for over 20 years!), are semi-evergreen and have beautiful flowers that attract pollinators. They need full sun or they’ll get floppy and a pH of 6-7. Mature plants can be divided. Pests, like deer and bunnies, will leave them alone. The flowers are edible, so there’s no need to pinch them off.
Another member of the carrot family so flowers are beloved by ladybugs. It’s also a larval food source for black swallowtail butterflies. It may go to flower quickly, but it also germinates quickly—in about 7 days—so it’s easy to always have some on hand.
A perennial, evergreen shrub, it’s native to the dry, rocky Mediterranean, so don’t be surprised if it only survives a few years in your garden. Give it full sun and really, really good drainage. When buying a rosemary plant, look at the label to see if it’s a “tender perennial” (probably won’t live very long here) or just a “perennial” (your chances for a long-lived plant are better). Carol suggests the variety ‘Arp’ for a good, hardy plant.
Another perennial, evergreen shrub that’s native to the Mediterranean, so its longevity may be iffy here. Like rosemary, sage likes full sun and perfect drainage. However, it is drought tolerant and pest and disease resistant. It likes a pH of 6-6.5 and needs more calcium than the average Maryland soil usually has, so you may want to mix some oyster shells or turkey grit into the soil.
Yet another Mediterranean perennial, evergreen shrub that likes full sun and well-drained soil, thyme tends to be a little hardier. There are many different flavors, like “Lemon,” “English” and “French,” so make sure you smell each when you buy. It makes a great edging in perennial beds or used between stepping stones. It has no disease or pest issues. Likes soil that is slightly alkaline (pH 6.5-7).