Question
Hi Richard,

We live in Boston and have two dwarf Alberta Spruce plants. The plants are about 3-4 ft tall and we have them outdoor (summer and winter) in 18-20" pots. We have had them since summer last year. Now large sections of the plants (especially around the lower half) are brown and dry - is that likely due to pests or just the stress from winter? I did see some whitish webbing on the leaves and the soil that I removed. With the weather warming they are sprouting green leaves - more so at the top. Should I be using some chemicals (or other means) to help control the damage from spreading during the spring/summer? What is the proper water management and care for these plants during summer and then during winter?

Thanks very much for your help.

Sanjay


Answer
the plants need to be repotted into larger pots. and they need to be put in a protected area(usually in a mulched bed on the east side of a building) for the colder winter months. this is probably why they look so poor now. the biggest problem i see w/dwf alberta spruce is that most people don't fertilize them. apply a good evergreen fertilizer(i like hollytone by espoma) once in the spring and again in the late summer. keep your eye out for spider mites(you'll see fine webbing w/grains of sand in it> -the mites). that sounds like what you removed already. during hot dry spells water at least once a week heavily(2-5 gal) to prevent stress on the plant. over dryness causes mites to attack them.  check w/a local garden center/nursery for more info. ask them what to spray after they ID the pest problem. spray accordingly when necessary. prune them yearly to prevent them from getting out of control. remove brown foliage as it appears.
water by weight. put a saucer under the pot. water and let the plant sit in the excess water for 5-10 minutes. after that time pour off any excess water in the saucer. pick up/or lean over the pot. it should feel heavy. don't water again until it feels considerably lighter in weight. outdoors check the plant everyday. watering frequency depends on many factors(sun exposure, type of plant, wind, day temps, etc.).

good luck
rick
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