Ask the Master Gardener: Forget winter — you can grow your own fresh herbs indoors right now
Growing herbs inside will essentially need the same growing conditions as those grown outside — sunlight and well-drained soil that is not too rich.
Dear Master Gardener: I purchased a basil plant at the grocery store, but there are no instructions on how to care for it. How much sun and water does it need?
Answer: This year in particular I’m feeling like I really live in Antarctica, the coldest, harshest place in the world with snow year-round. Luckily, we will get a reprieve from snow — maybe by May — but just because we live in a chilly, snowy climate doesn’t mean we can’t enjoy fresh annual herbs like basil all year! Growing basil (and other herbs) indoors can make your winter meals more flavorful. Those little packets of fresh herbs in the produce section of the grocery store can be expensive to buy and don’t last long, so growing herbs indoors on a sunny windowsill is a wonderful idea. Growing herbs inside will essentially need the same growing conditions as those grown outside — sunlight and well-drained soil that is not too rich. Place your basil plant in a south or west window where it will receive at least five hours of sun per day. Make sure it isn’t too cold or drafty. Water your plant (and any other herbs you may decide to grow indoors) when the soil feels dry to the touch or if the leaves droop. Never let herbs sit in water. Good drainage is important for growing healthy herbs.
Dear Master Gardener: Can I plant Astilbe in my garden that is pretty much in full shade?
Answer: You can plant Astilbe in full shade, but flowering will be reduced. For the best bloom and foliage color plant Astilbe in light to medium shade. These perennials need to be planted in soil that is well-drained, high in organic matter and kept moist throughout the growing season. Sprite is a hybrid in the Astilbe Simplicifolia Group that is quite shade tolerant and will flower in full shade. It gets about 12-18 inches tall, is hardy to 40 degrees below zero, and has pale pink flowers. Sprite has been growing in my shade garden for years and the deer have left it alone. Deutschland, in the Astilbe Japonica Group, is another good option for full shade. It is also hardy to 40 degrees below zero, gets 24 inches tall, and has lovely white plumes to brighten the shade garden. Most Astilbes are rabbit and deer resistant.
Dear Master Gardener: What can you tell me about a plant called bog rosemary?
Answer: Blue Ice Bog Rosemary (Andromeda polifolia) is a multi-stemmed evergreen shrub that is native to sub-Arctic regions of North America, Europe and Asia. It performs very well in cold climates and is hardy to zone 2a! In the landscape it works well as a groundcover, edging plant, or in a rock garden. It prefers moist, acidic soil. Plant it in full sun to part shade. It is a long-lived plant that reaches approximately 2 feet in height and 3 feet in width at maturity. Blue Ice Bog Rosemary has beautiful powdery blue, needle-like foliage with dangling clusters of pinkish-white flowers that bloom in spring.
Dear Master Gardener: I would like to make a dish garden with a southwestern theme and was wondering what plants would fit the bill.
Answer: Succulents are great plants for a dish garden. Succulents refer to a broad category of plants, which include cacti. They have thick fleshy leaves or stems, which serve as water storage organs to ensure survival under very dry conditions. In addition to cacti, some other succulents you may want to consider are: jade plant, snake plant, medicine plant, century plant, Kalanchoe, Echeveria or panda plant. These plants do very well as houseplants because the relative humidity in most homes is usually low. Mix one part potting soil with one-part coarse sand and sterilize. You can sterilize potting medium by moistening the soil mixture, covering it with aluminum foil to keep it from drying out while being heated, and place it in a 200-degree oven for about 30 minutes. Or, you can purchase a soil mix specifically for succulents. These plants require a bright sunny window.
When you group succulents and cacti together in a dish garden, choose plants that have a similar growth rate and similar water requirements. Since dish gardens rarely have drainage holes, it is important that you do not over-water the plants. Even if you have some pebbles at the bottom of the container to allow some drainage, any excess moisture will be drawn back into the soil and keep the roots moist for too long, possibly causing fungal or bacterial rots.
Dear Master Gardener: I think my English ivy has spider mites. Is there a way to tell if they are spider mites and what should I do about the insect problem?
Answer: If English ivy is underwatered, red spider mites can be a problem. They are a common houseplant pest and like a warm, dry environment with low humidity. Plant leaves will have a stippled appearance. Look for little weblike structures on the underside of the leaves. You can test for spider mites by holding a white sheet of paper underneath the leaves and tapping the vines sharply. Look for tiny specks crawling on the paper. If your ivy has a lot of spider mites, you may want to move it to a cooler room away from other plants to avoid infecting them. Keep the soil moist but not saturated. Wash the plant off with a forceful spray of lukewarm water. You will have to do this repeatedly. You can swish foliage in soapy water, but you need to be careful not to use too much soap — just a drop or two of mild dish soap. Insecticidal soap and horticultural soap are usually very effective. When I have a severe infestation with most of my plant covered with spider mites, I place it in a plastic bag and toss it in the garbage.
You may get your garden questions answered by calling the new Master Gardener Help Line at 218-824-1068 and leaving a message. A Master Gardener will return your call. Or, emailing me at firstname.lastname@example.org and I will answer you in the column if space allows.
University of Minnesota Extension Master Gardeners are trained and certified volunteers for the University of Minnesota Extension. Information given in this column is based on university research.