NC Garden: Low-light herbs & edibles, toxic plants for pets

We’re inching closer to the warm weather planting season, and readers have questions about planting edibles (or just keeping them inside), enjoying ornamentals, determining the best time to put warm-weather vegetable plants in the ground and composting in small spaces.

The News & Observer spoke with Ashley Troth (an NC State Cooperative Extension agent at the Durham County Center) and Rhonda Sherman (an NC State Extension solid waste specialist) to answer readers’ questions from the month of April.

Here’s what you wanted to know:

Which plants are harmful to pets?

What plants do I need to avoid if I have outdoor cats/dogs?

Troth answered:

“If you start reading about it, a very large number of ornamental plants around here are toxic.

My advice would be to watch your pet outside and see how they interact with your plants. Most animals figure out quickly if they don’t like something.”

Troth, who has cats and dogs, has found that indoor animals get more excited around plants, while animals allowed to roam around outside don’t care much for them.

“Rhododendrons and azaleas are supposedly toxic to animals. I have them in my yard right now, and my pets have never had a problem,” she said.

Troth recommends consulting the American Society for the Prevention of Cruelty to Animals’ (ASPCA) Toxic and Non-Toxic Plants List. For the full report, visit aspca.org/pet-care/animal-poison-control.

But also don’t let your animals wander around your edible garden: “I’m just saying, you don’t want your animals going to the bathroom on stuff you want to eat,” she said.

Can you compost in a small space?

How can I compost in an apartment? What about a dorm room?

There are a few ways to compost when you’re in a small space, Sherman said.

▪ Use a convenience center to drop off food waste: Wake County has food waste recycling centers in four locations. Two are in Raleigh, one is in Apex and one is in Wake Forest. For more information, visit wakegov.com.

“It’s too costly to add to all 11 convenience centers, and Wake County is actively seeking businesses to host pilot sites,” Sherman said. If you’d like more information, contact Bianca Howard at [email protected].

Orange County has five food waste collection sites. Three of these include the Carrboro, Chapel Hill and Eno River Farmers Markets. For more information, visit orangecountync.gov.

Durham County has a pilot site for food waste drop off in Walltown, but there are no other drop-off sites in Durham. For more information, visit durhamnc.gov.

Johnston County does not have a food waste drop-off program.

▪ Recruit the worms: “Try vermicomposting!” said Sherman, who is a globally recognized vermicomposting expert.

Vermicomposting is composting using earthworms. You’ll need an earthworm bin, bedding, water, composting earthworms and the stuff you want to compost, like food scraps and other organic materials.

For a full guide to vermicomposting, visit content.ces.ncsu.edu/worms-can-recycle-your-garbage.

▪ Use a private service: Services like CompostNow can take away your compost for a small fee each month.

▪ Composting for college students: “People contact me all the time asking if they can bring their food waste to NC State and compost it here, and I have to say ‘No! You can’t!’ That service is for residential students only,” Sherman said.

If you’re a residential student at a local university, here’s how you can compost from your dorm.

UNC-Chapel Hill: Residents at Carolina can get a composting bin from their community main office, then they can empty it out weekly into their designated green or black compost cart. For more information, visit facilities.unc.edu/departments/waste-reduction.

Duke: Students can bring their food waste to a few drop-off locations around campus. For more information, visit facilities.duke.edu.

NC State: Students can drop off their food waste at a number of drop-off locations around campus. There’s even a map for pizza box composting sites! For more information, visit recycling.ncsu.edu/compost.

“We do have a compost bin/pail program at select residence halls with kitchens where students can collect their compostables in the bins/pails and then take those and empty them in the compost dumpsters,” said Adam Bensley, the school’s waste diversion coordinator.

“Student Government also gave out the kitchen pails this year to students, and we have also had student-led initiatives to provide jars to students who take a training. We do not offer any type of option for students to actually perform the composting of their materials inside of their rooms.”

NC Central: Students, faculty, staff and community members are welcome to drop off their food waste at the compost bin in the Campus Community Garden.

“NC Central has a compost bin in its Campus Community Garden, which is available to faculty, staff, students and the Durham community. Located between the Mary Townes Science Building and the Biomanufacturing Research Institute and Technology Enterprise (BRITE), the university’s garden is composed of 20 beds of vegetables, fruits and herbs,” said NC Central’s communication director Quiana Shepard.

Wake Forest: Students living on campus at the North Campus Apartments can opt into the composting program for free. The university is working to expand this program to other residence halls, said WFU’s waste reduction specialist Sophie Wimberley. Students can also use Gallins Family Farm’s publicly available options by bringing their organic waste to the Cobblestone Farmers Market.

Which herbs don’t require full sun?

Are there any herbs that don’t require full sun? I want to grow edibles in my apartment, but I don’t get full sun. What can I grow, and how much space will I need?

Troth answered:

“The bottom line is no, but there are workarounds. Herbs are just like vegetable plants. We’re asking them to do a lot — we want them to grow so much that we can take extra, and they are still fine. Without sunlight, which is how plants are powered, we can’t accomplish that.”

If you don’t have an area with full sun, you might have a south-facing window (which gives you the most light, while a north-facing window gives you the least light). You can go to your market, gardening store or even supermarket and get a potted herb plant that you can leave there to get as much light as it can, she said.

“Keep your plant watered and with as much sun as it can get, and enjoy it while it works. You won’t be able to make a batch of pesto every week, but you can pluck some leaves for garnish,” Troth said. “Expect four to six weeks of this, then when the plant is suffering from low sun, throw it in your compost pile.”

You can also get a small tabletop grow light: “It’s amazing how strong some of the LED grow bulbs are now!” she said.

Remember, The Zen Succulent’ s co-founder Megan George Cain told us in an earlier Gardening Guide that every space can house a plant, it’s just about getting the best plant for your environment. Some plants can even survive in a windowless bathroom with no light at all!

For more on growing herbs on a windowsill (and finding houseplants when you don’t get enough sun), visit newsobserver.com/living/article260419682.html.

What if it freezes overnight when my plants are already in the ground?

It’s been cold this week, and I’m not sure when to plant anymore. I was going to plant around this time (mid/end of April) but now I’m worried. When should I plant now? What if people already put their plants in the ground?

Troth said:

“If you already planted and you know there’s a cold coming, you can cover plants with a light cloth. If they’re in containers, a bucket can work. The key is to ensure the cloth or bucket doesn’t touch the plants themselves, but it’ll act as a barrier or an envelope so the heat stays inside.”

While the average last frost date is the middle of April, around April 15, it’s a safer bet to plan to plant in early May, since temperatures are likely not to dip below 40 anymore, she said. But if they do, get your sticks and a sheet, and make sure you keep your plants protected overnight.

“I like to wait until mid-April then look at the 10-day forecast. If I don’t see temperatures below 40 for the next 10 days, I can assume I’m good,” Troth said. “But I make sure my buckets are clean and my sheets are ready. Just an old set of bed sheets works well for this. All you should need are sticks, a bed sheet and some ingenuity.”

Note that urban areas are generally five to 10 degrees warmer than rural areas, as concrete provides some insulation. In her part of downtown Durham, Troth expects temperatures a bit higher. Suburban areas with sidewalks can be a few degrees warmer than rural areas with very little concrete, she said. Take this into consideration when thinking about planting temperatures.

What should I plant in May in North Carolina?

What can I plant in May?

Troth answered:

“Basically everything! All warm-weather plants are perfect to plant in May. Shrubs and trees are better for cooler times of year, since they require a lot of water and it’s starting to get hot, so you’ll need to be really on top of their watering if you want to plant those now.

“One of the best things about planting in May is everyone is excited about planting so the nurseries know to get all the things. Aside from shrubs and trees, a lot of things take place in May really well, and you can get almost whatever you want at your local nursery,” Troth said.

Here are some tips when thinking about the warm-weather plants to grow:

▪ Plant native: Add pretty pollinators and colorful perennials to your summer garden! But make sure they are native. Non-native plants will take nutrients and resources away from other plants, while native plants will help all plants thrive and live in harmony.

For more information about native plants in NC, visit gardening.ces.ncsu.edu/native-plant-resources.

▪ Visit your garden center every season: “It’s not hard to convince gardeners to go to their garden centers more often,” Troth said. “If you go at the start of every season, you’ll get familiar with a selection of plants that are best for that time of year.”

▪ Ask your Extension agent: If you need help finding a garden center, or want to chat about what would be best to plant in your yard, reach out to your county’s NC State Extension office. Master Gardeners and volunteers can answer your questions and work with you one-on-one.

To find your local county center, visit ces.ncsu.edu/local-county-center/.

Here’s what NC State Extension’s Central NC Planting Calendar says can be planted in May.

(Note: Pay attention to planting instructions, which includes transplanting, starting from seeds indoors, growing in a pot and more.)

• Basil

• Beans (lima/bush, lima/pole, snap/bush and snap/pole)

• Collard greens

• Sweet corn

• Cucumbers

• Eggplant

• Kale

• Kohlrabi

• Leeks

• Cantaloupe

• Watermelon

• Mustard

• Okra

• Parsnips

• Peanuts

• Peas (field/southern)

• Peppers

• Sweet potatoes

• Pumpkin

• Radishes

• Spinach

• Squash (summer and winter)

• Sunflowers

• Tomatoes

• Turnips

Questions about backyard gardening?

Do you have questions about your backyard garden? Any stories you’d like to see about gardening topics? Tell us here! Or email [email protected].

This story was originally published April 23, 2022 8:12 AM.