Winter is here, but gardening questions keep coming in to Ask an Expert, an online question-and-answer tool from Oregon State University’s Extension Service. OSU Extension faculty and Master Gardeners reply to queries within two business days, usually less. To ask a question, simply go to the OSU Extension website and type in a question and the county where you live. Here are some questions asked by other gardeners. What’s yours?
Q: We moved into our house in May and had a really high-water bill over the summer. I wonder if it is due to watering our yard. It is nicely landscaped with shrubs and small trees and no grass. Would replanting with native plants allow us to water less? If so, where can we get help with that? Or maybe we can just water less. How can we find out how much we really need to water? If you can't help with this, we appreciate any direction you can give to those who could. – Multnomah County
A: Watering during our drought period (July-September) can really drain a budget. Here are a few ideas to control water use
1. If you have an automatic watering system have it inspected for leaks, check the watering schedule to make sure it matches your plants needs and tune it up for the coming summer. There are also WIFI-based EPA "Water Sense" Irrigation Controllers that operate from your cell phone and allow you to not water if it's raining or add an additional watering cycle during extended heat periods. If you use a manual system, use drip units or soaker hoses. Sprinklers lose a lot of water to evaporation.
2. Examine your soil for drainage. Water should be absorbed into the soil fairly quickly, and not pool and run off. You can also check moisture levels with a screwdriver, which should go into moist ground fairly easily. In dry soil it is difficult to insert the screwdriver.
3. Mulch your plants with 2-4 inches of mulch (compost, bark chips, etc.). This makes such a difference for your plants. By covering the soil, mulch retards surface evaporation, and moderates soil temperatures. By blocking sunlight, it discourages weeds, and as soil organisms breakdown the mulch they add organic material to your soil. Your plants will love it.
4. Organize the plants in your yard so plants are grouped by water needs. This is much more efficient use of water – and your plants will do much better as well.
5. Select the correct plants for your conditions. Often, but not always, these are native plants and we have many beautiful natives in our area. Exploring plant choices is great fun. I would suggest starting with the Great Plant Picks web site. You'll find pictures and growing information of many stellar plants. It is created and managed by Northwest nurserymen, so the information is specific to our area. Its plant lists include drought-resistant plants and Pacific Northwest native plants. There are many native plant sales in the area in April especially (Hardy Plant Society Hortlandia Sale, EMSWCD Native Plant Sale, and others).
These programs are helpful and very interesting. Water Sense Landscaping Tips; 7 Basic Steps to Creating a Water Efficient Landscapes; 100+ Ways to Conserve Water. I encourage you to explore these programs and others. Water conservation is a process and you can learn from many sources. – Anne Schmidt, OSU Extension Master Gardener
This wild blackberry plant was found growing near Mount Scott.
Can you identify this wild blackberry plant?
Q: I live on the north side of Mt. Scott in outer east Portland, at about 650 feet elevation. I walk down the street to harvest Himalayan blackberries, and I have cultivated native Pacific blackberries by weaving those vines through my wire fence out back (my backyard borders maple-tree woods). While hiking through these woods, I've come upon a berry that looks like a blackberry, but it isn't Himalayan or Pacific – its berries ripen much later than Himalayan, their vines are reddish and not nearly as stout as Himalayan, and the leaves have sawtooth edges.
I haven't seen any other plant like this in my hikes through these woods. The plant is confined to an area of 10 feet in diameter, and sits on the southern edge of the woods and adjacent open space. My Google search suggests it is a European blackberry. Can you tell me what this plant is, and why it hasn't proliferated like Himalayan or Pacific blackberries? – Multnomah County
A: We believe this to be a Rubus laciniatus, which is described here. I believe the one you were suggesting is Rubus fruticosus, described here.
Both are invasive, but may be unable to compete with the Himalayan blackberry (Rubus armeniacus) described here. – Kris LaMar, OSU Extension Master Gardener
Transplant blueberry bushes from March through May. File photo Joel Bissell | MLive.comJoel Bissell | MLive.com
When is the best time to transplant blueberries?
Q: I have a row of blueberry bushes in my back yard that need to be transplanted or moved from their current location. When is the best time to move them? – Multnomah County
A: The following OSU Extension article recommends October or March through May. – Kris LaMar, OSU Extension Master Gardener
Black spots on leaves could be bacterial infection.
Gifted plant developing black spots on the leaves
Q: I got this guy as a Christmas present and a few days later noticed that there were dark spots developing on two of the leaves. I thought I would keep an eye on it but it seems to have rapidly spread and is now larger on the two initial leaves and has spread to multiple leaves as well. Additional spotting can also be seen on the stems. Is this bacterial leaf spot? – Multnomah County
A: Your diagnosis of a bacterial attack on your new houseplant (split-leaf philodendron or Monstera deliciosa) seems likely. Bacterial diseases are encouraged by high humidity, wet leaves, and poor air circulation around the plant. You may want to cut off the affected leaves to prevent spreading. A copper spray can also help keep this disease in check.
Another possibility is a fungus disease. In that case, you might see a concentric ring pattern in the brown spots. I do not see this in the photos, but you might see it in person. Again, providing good air circulation and keeping water off the leaves (as with a bacterial disease), and a spray with a copper fungicide (again, as with a bacterial disease) could be in order. – Claudia Groth, OSU Extension Master Gardener
More tips from Master Gardeners
How to make hand-cast stone pots
How to propagate plants from cuttings
Put out the welcome mat for birds this winter
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