Why Weed the Green Roof?

 

Weeds blocking access to the composter.  Planter waiting for a spot.

I had this question, recently, and figured others were likely wondering the same thing!

A green roof is not a wild roof because there are structural issues.  Seeds travel on the wind and by bird poop.  As much as we would love to see milkweed for the monarch butterflies and a small tree for birds, the roof cannot support the weight or the invasiveness of the roots. 

A green roof has a variety of plants that are sturdy, drought resistant and have really shallow roots.  Deep roots could break through the roof membrane.  If that happens, there will be all kinds of structural issues with water getting where it is not supposed to go.

There is a contractor for our building who only takes care of the section of the green roof that we don’t have access to.  The original contractor was responsible for the entire green roof.  Now, as with all other CCOC rooftop gardens, the Metcalfe gardeners receive a plot in exchange for keeping our section of the roof weeded and clean. 

Weeds behind planters with a planter nobody in the community garden on the ground wanted.  Apparently, the roof won't handle the weight of the planter in the winter, yet it sits there looking like garbage.  By managing our green space, maybe we won't become the dumping ground. 

At the meeting on Sunday 23 June 2015, the Metcalfe gardeners recognized that there were many deep rooted weeds and that the roof looked unkempt as opposed to wild.  

Patio tiles with weeds growing.  Eventually, Mother Nature will crack our tiles and the roof will look even more unkempt.  We have a new tool to make weeding this easy, though!

Our rooftop has the potential of being a beautiful, organic, food secure habitat for pollinators and people, while lowering the carbon footprint of the community below the roof.   We also want it to be easy to maintain. 

We came up with a concept, with the view to filling in the details in the near future.   The group decided which plants we definitely wanted to keep.  Evelyn was supported in wanting a section to be for wild, native plants.  Overwhelmingly, the group wanted to add plants that were either edible or valuable food sources for pollinators.  The CCOC Garden Facilitator let us know that the roof was not toxic for growing food, but that it is not nutrient rich; this will be a challenge in selecting plants that will thrive.

Michael and Robert were the first to start weeding (14 hours in a small area);  they found one section with ridiculously invasive roots.  It became evident that the plan to get rid of almost everything and start again was a sound decision. 

Over the next couple of weeks, while we are weeding, ideas will flow.  At the next meeting, we will zero in on which plants we want and then figure out how to get them.  Those who can’t make the meeting – it is summer vacation time – are encouraged to send suggestions via the rooftop coordinator. 

We weed the roof to make our home lovely and safe.  

Sorting Compost

 Healthy Ingredients in the Compost 

Healthy Food for the Vegetable Garden

Healthy Food on Our Plates

Bin 1 Cooking What to add? NOTHING!!!!   Except maybe coffee grounds without filters. What’s happening? Bin 1 has been layered with dirt, green waste and brown waste.  Throughout the season, it will get poked to keep the air flowing and watered to feed the critters transforming our yard waste into compost. The activity in the decomposing process will actually make the composter hot!  On a cool morning, you may even see steam rising from it.  This is why it is labeled “cooking”.

Bin 2 Green Waste Nitrogen rich waste What to add?   Leafy Garden Waste Flexible Stems and Roots Grass Coffee grounds and tea without filters NOT COOKED Vegetables and Fruit Waste Corn leaves and silk What’s happening? Just filling up so we will have green waste we can layer when bin 1 gets emptied in the fall. Some decomposition will happen. If Bin 2 gets stinky, it is suffocating and needs air.  Just turn it with the pitch fork.

Bin 3 Brown Waste Carbon rich waste What to add? Anything woody, hollow stalks or really thick garden waste. Sunflower stalks Corn cobs that don’t have butter or salt on them! What is happening? Just filling up so we will have green waste we can layer when bin 1 gets emptied in the fall. Brown waste takes MUCH longer to break down than green waste. Bin 3 won’t see much action during the summer, but come fall clean up, it will fill up quickly!

Do Not Add the Following to the Composter or We Will Get Sick!!!!

No cooked food;  it doesn't matter if it is vegan, vegetarian or meat.  If it is cooked, it will contaminate the composter, which will contaminate the plants that will end up on our plates!

Also Absolutely NO

Oil         Animal Waste    Eggshells   Bread(because it is cooked)

Plants that are diseased or have flowered because 

our composter won't get hot enough to kill them;  we don't want them travelling through compost to our gardens.

Animal Poop and Kitty Litter and Animal Bedding (rabbits, hamsters...)

Meat, cooked or uncooked!  Meat in compost has lead to e-coli outbreaks!

Any kind of oil

Peanut butter or any kind of bread

Butter because it is an oil and an animal product!

All of the above, except pet waste, can go in the city composter because the city compost gets a lot hotter than ours will when it is cooking.  

Weed Dance!

Gotta love the idea of singing and dancing while weeding!  Anyone down to try this on the rooftop?  Just don't break the roof membrane or those of us on the eighth floor will be rather wet!

Video

Tomato Leaf Harvest!

Healthy, bushy tomato plant that could do with pruning to prevent blight.

For those of you with tomato plants, you may be ready to prune!  If the plants are super bushy, the air might not be circulating well inside the plant.  This could lead to tomato blight. 

Cut off some of the extra branches that don't seem to have fruit starting. 

Nip off any new branches starting between the main stem and an existing branch. 

The healthy leaves can be used as a spray to combat aphids!  If there are no aphids in the garden, keep the leaves so they are on hand if we need them. 

Option A:  Chop them up and freeze them. 

Option B:  Dry them by hanging them upside down. 

Option C:  Contact the rooftop coordinator who has a food dryer and can dry the leaves in a couple of hours. 

Tomato Blight

Early Tomato Blight:  Source Cornell University Website

Tomato blight is a black fungus that grows on the leaves and stems and can destroy your tomato plants.  

Usual Cause  Warm days and cool nights.
                           Too much moisture.

Prevention

Keep the air circulating!  
1. Once the plant is growing, chop off the lower leaves so they don't drag on the ground and 
     begin to rot. 
2. Cut off extra branches, usually the ones popping out between the stem and an existing           branch. 
3. Apply the Tomato Blight Buster every couple of weeks.  See recipe below.

Watering
1.  Don't over water.  If you see yellow leaves, you are overwatering.  
2.  Water from below the leaves.  The rain hits the leaves, but not as hard as watering from 
     hoses and watering cans.  
3.  Water in the morning, if possible or as early in the day as you can.  You want the sun to
     dry the leaves. Don't water at night!

Treatment

1.  Cut off ALL the leaves, stems, and fruit that have black spots and dispose in the garbage, 
     not the compost.  The compost won't get hot enough to kill the blight and you will end up 
     infecting new plants next spring!

2.  Prune so that air is circulating. 

3.  Use an organic recipe to treat the rest of the plant. 

Tomato Blight Buster Powder

Mix together: 
3 cups compost
1 cup non-fat skim milk
1/2 cup epsom salts
1 tbsp baking soda

Sprinkle on the ground around the plants. The original source for this recipe recommends applying the mixture every couple of weeks over the season. 

Blight Spray

1 litre of water
1 tbsp baking soda
1 tbsp vegetable oil

Mix in a spray bottle. 
Spray all the leaves, top and bottom.
Spray the stems.
Spray the ground. 

Avoid spraying in the hottest part of the day because that may stress the plants.  Apply in the early morning or evening. 

Tools for Pest/Disease Control

Bottles to use for homemade remedies are in the garden room.  Please label the bottles as you create new recipes. 

A bottle of dish soap is also available. 

Wet Season Issues

Watch for signs of too much water!  It is rather odd to talk about this on a rooftop, but we have had a lot of rain since the beginning of the season. Normally, drought conditions occur on rooftops and on balconies.   However, we have noticed two symptoms of too much water. 

    Slugs

   As with most pests, they love the night life.  A few slugs is no big deal as every garden needs a balance of insects.  However, if the slugs are really chomping down, put out a tuna can at soil level and fill it with beer.  The slugs will drown themselves in it. 

   Blight  

Rhubarb Blight

   This really refers to a variety of fungi that attack lots of plants, tomatoes in particular.  If you see discolouration on the leaves, it might be blight.   Typically, black on tomatoes, red on rhubarb. 

Prevention

a.    Keep large/dead leaves off the ground and make sure the air can circulate through the plant.  Tomato cages are helpful when it comes to air circulation.

b.    When you do water, try NOT to water the leaves.  Water directly onto the soil, if possible, using a gentle setting on the nozzle so that water and dirt don’t splash up onto the leaves. 

White Fly

White Fly on the Rhubarb in Plot 4

I have lots of holes in my rhubarb leaves, so I went up at night to see what was eating them.  I found this white fly!  

The organic solution is spraying with soapy water.

There will be a labelled spray bottle in the garden room if anyone else needs to spray.   It is also good for red spider mites and aphids. 

Welcome!

The Metcalfe Garden is a community garden on the rooftop of the Beaver Barracks eight-storey building.   The rooftop community garden is managed and maintained by the tenants and very well-supported by CCOC. 

The Metcalfe Rooftop Garden Blog is a central information portal for the gardeners.  Information on weeding, pest control, meetings, plants, concerns, and various gardening tips will be posted.  Although the rooftop coordinator manages the blog, any of our rooftop members are welcome to write a post or upload pictures to the blog.  

Any posts referring to specific gardeners must be positive, not use last names, and have permission from the gardeners mentioned. Clean laundry only.