Monday, December 10, 2012

Grow Lucious Rosemary in Containers

medicinal herbs rosemaryRosemary absolutely shines as a beautiful potted ornamental as well as a culinary herb. Its Latin name, Rosmarinus officinalis, means "dew of the sea." Rosemary is native to the Mediterranean. It thrives in containers under less than perfect conditions.  In fact, Rosemary's fragrant essential oil becomes more potent when the plant suffers from a little neglect. Rosemary is not a heavy feeder. However, it benefits from fertilization in early spring with a fish/kelp emulsion.  As rosemary dislikes constantly soggy soil, terracotta pots are recommended. I have found  that rosemary will thrive in any container as long as there is a drainage hole in the bottom of the container. Rosemary benefits from less frequent watering in winter.



  Wintering Indoors

Rosemary
In this part of the country, the upper Midwest, temperatures can dip well bellow freezing. My rosemary plant has to spend winters indoors. It's so easy to care for. The container pictured here is made of ceramic. As soon as temperatures threaten to drop below 40 degrees, I bring this potted rosemary plant inside.  It spends cold months in a southern facing window that receives 8 hours of daylight & very little sun. The temperature is keep between 62 & 65 degrees.  My rosemary plant is moved  back outside as soon as temperatures rise and there is no possibility of frost


                

  Potential Problems 

Although it has never affected this 7 year old  rosemary plant, powdery mildew can become a problem indoors. Powdery mildew is a white, powdery fungus that sometimes develops when humidity is high and not enough air circulates around the plant. Although it can be a problem, powdery mildew is not fatal to the plant. The plant will frequently become weaker when affected by powdery mildew. Since powdery mildew occurs under high humidity conditions, it can be controlled with a few preventive measures.  Here are some ways to prevent powdery mildew: 1.Allow the soil to become somewhat dryer before watering.  2 If possible, keep the plant in sunlight. 3.Operate a fan near the plant to increase air circulation.

Aphids or spider mites can be of some concern during winter as well.  Aphids are best controlled by ridding the plant of them before total infestation occurs. To control aphids and mites, I make a homemade insecticidal soap consisting of 3 or 4 drops of dish detergent plus 28 ounces of water.  As a preventive measure, this mixture is sprayed on the rosemary plant weekly during winter months. Of course there are commercial verities of insecticidal soap available at discount stores and nurseries.

Maintenance

Most gardening publications suggest that potted plants be transplanted yearly due to soil deterioration.  This rosemary is transplanted once every 2 or 3 years. It  has not suffered any ill effects.  On the other hand, transplant your rosemary when it appears to need watering more than usual or becomes extremely root bound.

Springtime is an ideal time to transplant. Ordinary potting soil is sufficient.  As with most container plants, transplant when the plant outgrows its container. The size of the rosemary plant can also be controlled by root pruning. Cut off a few inches of the roots from the bottom and sides of the root ball. Replant in the original container. Trim a portion from the top of the plant in order to decrease stress on the plant's roots. Give the transplanted rosemary time to recover from the stress of transplanting.  When new growth appears, snip as usual.  Use snips from your rosemary plant to make delicious culinary creations. Rosemary adds flavor to lamb, veal & chicken dishes.  Let your imagination sore!