During the current warm and dry spell, Master Gardener Ed Buyarski issues his usual advice to vent your greenhouses and water your plants.
In this week’s edition of Gardentalk, Buyarski described how the temperature in his greenhouse recently pegged the gauge at above 120 degrees. And, his greenhouse is covered by clear single-layer plastic sheeting, not double-paned windows which can more effectively retain heat.
He suggests leaving the doors and vents open to ventilate your greenhouse in warm or humid weather.
Buyarski also described how one local gardener started watering her hanging tomato plants twice a day because they dried out so quickly in Juneau’s recent 70-85 degree temperatures.
Also, a reminder that the Southeast Master Gardeners Garden Tour will be from 11 a.m. to 4 p.m. Saturday, June 23. Seven gardens will be on display.
You can find a map and more information about tickets at this page.
Listener questions on garden bed covers and rhodies –
Buyarski answered a few questions submitted by local gardeners.
John wrote: “I have beds (4×16) and salvage single-pane storm windows (metal frames). Building covers, leave lots of vent to dry or little to hold heat?”
Buyarski recommends John consider the plants that he wants to grow before constructing the framework to hold the windows.
They will work better than clear single-layer visqueen to warm up the plants and the soil, but Buyarski said designing options for adequate air flow and ventilation is essential to prevent fungus development during high humidity.
“Whether that be screens on the ends or if he can somehow put hinges on the windows to lift one up on each end to let the hot air out while also still shedding rainfall,” Buyarski said.
Julie wrote: “We live in Gustavus and think that our Rhododendrons are beyond help. The leaves are covered in rust-colored spots.”
Buyarski said it sounds like a fungus.
“Certain rhododendrons get those brown fungus spots,” he said. “It is a variety issue, unfortunately.”
Buyarski suggests Julie research rhododendron spots, fungicide treatments and fungus-resistant rhododendrons if she has internet access.
He recommends that Julie do not use the usual fungicide treatment of a baking soda spray since the sweetness can have an adverse affect on rhododendrons.
It’s also essential that any old, dropped leaves be cleaned up and removed.
A layer of sand or spruce needles placed under the rhododendron will prevent more fungus spores from splashing up to new leaves on the plant.
You have a gardening question of your own? Go to this page, fill out the form on the right, and we’ll try to answer your question on the air.
