Powdery Mildew

Posted on July 26, 2011 by halifaxgardennetwork

Poking around the office garden today and I discovered our beautiful cucumbers all have a bit of powdery mildew. Rather than go back inside and get back to my email I spent a bit of time with them hoping to prevent the spread.

I thought I’d share my tactics, and ask you to share your tactics, and together maybe we can defeat the powdery mildew.

What is powdery mildew you ask?

It is a plant disease that will kill off the leaves and flowers of your plant. First you will notice little white or grey spots on your leaves and stem of the plant, then they will begin to turn yellow and shrivel up. The flowers will also shrivel and fall off the plant.

The book, The Rhodale Vegetable Garden Problem Solver, explains:

Powdery mildew spores germinate on dry leaf surfaces when humidity is high; the spores can’t germinate on wet leaves, and they don’t germinate very well on leaves in full sun. Thus, the disease tends to be a problem in dry climates or during dry spells, taking hold in areas of dense, shaded foliage where air circulation is poor. pg. 337

Leaf with Powdery Mildew

How do you know if it is Downy Mildew or Powdery Mildew?

The two are quite similar, however downy mildew happens during long periods of wet, cool weather. It happens very quickly and your plant will look like it has been frosted overnight. The symptoms look quite similar, however the furry spores appear on the underside of the leaf instead of the top of the leaves and the spores disappear when it is dry.

Milk and Water spray

So this is what I do.

First I take off all the diseased leaves. Sometimes I leave the really big green leaves that have one or two spots on them. I have a feeling this is probably not a good idea, as they host the spores, but I just can’t bear to throw away those lovely leaves. I’d recommend taking off all the diseased leaves if you can bear it.

Then I spray the leaves and stems of the plants with a mixture of 1 part milk to 9 parts water. I try to do this everyday.

I have also read that baking soda mixed with water, and compost tea or comfrey tea are also helpful.

Remember

Get rid of diseased plant material. If you don’t have a hot compost pile that will kill off the spores, then find somewhere else to dispose of the plants. The spores will overwinter and are spread by the wind.

Do you have any tips? Send them in at halifaxgardennetwork@gmail.com

Gardens About Town: Gorsebrook Garden

Posted on July 23, 2011 by halifaxgardennetwork

Garlic Scapes in all their un-trellised wildness.

After I posted about our EAC garden’s new trellis I had a chance to bike around town and peek in to see how other gardens were growing. It had been a while since I visited the Gorsebrook Garden, that is part of the … Continue reading →

Building It Up and Giving Some Support

Posted on July 19, 2011 by halifaxgardennetwork

As the heat of the summer grows (or slowly ebbs and flows), I start to see the results of my undone to-do list. In the garden the things you leave for tomorrow often end up in wildness, anarchy and a particular kind of beauty. This year I am trying to be better about doing less of my job on the computer and more of it out in the gardens in our city.

Our office (the Ecology Action Centre) has amazing little pockets of garden around our back deck and in the spirit of my new goal I have been giving it more attention than usual. The results have been pretty amazing both in the garden and in me, as I work on getting over my fears of building and general feelings of un-skilled-ness.

This month I finally took some time to properly stake the tomatoes and got some help and to build a trellis along our front sidewalk. On the trellis we are growing beans, squash, and cucumber and I staked our tomatoes with 6 ft. hardwood stakes that I bought at Canadian Tire. Here is some information, photos and links about both of these things.

Supporting Tomatoes

I like staking tomatoes because it is easy and I think it looks nice. Before you start make sure the stakes are at least six feet tall to give the tomatoes enough to grow on. When I stake the tomatoes I like to pinch off the suckers, which are the shoots that crop up between the main stem of the plant and the branches. This helps keep the plant a manageable size and puts more energy into producing big yummy fruit.

Suckers: Now You See It

Now you Don’t!

Then I tie the stem of the plant to the stake to secure it. I do this by first attaching twine to the stake nice and tight. Then I attach the twine very loosely to the plant stem, leaving lots and lots of room for it to grow throughout the season.

Leave a hopeful amount of room when you are tying the twine around the stem.

If you’d like something more substantial, you can build an A frame trellis and use string to train the plants up as another option. (See our links down at the bottom for A frame designs).

Tomatoes are staked and all in a line

Beans, Cucumber and other Trellis Loving Plants

There are many ways to build a trellis for taller growing plants like beans. The main things to keep in mind as you build is that it is sturdy, secure and big enough for the plant you’d like to grow on it. You will want to find a way to secure the structure in the garden depending on where you are placing it in your garden. If it is a bed in the middle of the garden you can bury the base of the trellis nice and deep, packing the soil around it tightly to that the structure is secure. A frame designs are great for this situation. If you are gardening in raised beds then you can attach the trellis structure to the side of the bed.

In our case we are growing the beans up a large wall, and so we built a very simple flat frame and attached the it to the vinyl siding, making sure to waterproof the holes with rubber washers and caulking. We then used jute twine to string vertically on the frame for the beans and cukes to grow up. It didn’t take much time at all and since we had mostly scavenged lumber and supplies, we only had to buy the twine.

Here are some photos of us building our trellis…