Watering in the warm October

We have had an incredibly warm October, with some significant wind. The soils continue to be warm and many still-green plants in my garden are still blooming, so I know they need water, though at  a reduced rate. 

I had the most incredible gourd harvest off my south-side trellis because of the weather.

You should have your soils moist going into winter, whenever it comes. If you have had your irrigation system blown out already, then unfortunately you will have to haul hose like me. But we have been gifted with a fabulous Fall, so this seems a small payback for our gardens’ lingering beauty.  

Q&A: Repotting a succulent

Someone asked me recently about repotting a succulent:

"I'm not sure if you can answer this, but I was repotting a succulent and in addition to the main plant and a few chicks/pups growing from it, there's also the plant in the photo. It's the same kind as the main plant, but the young plants seem to be all on one stem, instead of runners. Should I break it up or treat it like a single plant?"

I think those are branches, not babies. They might root if you broke it up, but I would just repot it as one plant.

If you have more questions, feel free to email me at chaosinthegarden@gmail.com!

Cutting back your garden for fall

We have had our first hard frost and now comes the hardest part of fall – cutting back my garden.

Some people cut their plants back and clean up the garden all at once. I prefer to do it gradually, for a couple of reasons: it helps me adjust to the change of appearance, and not everything dies at the same time.

There's freeze damage on my tomato, but the undamaged
yellow calendula (pot marigold) will continue blooming for
several weeks.

The process of garden clean-up is most important if you have insect pests, like aphids or spider mites, or diseases, like powdery mildew. Those perennials and annuals should be cut back to the soil line early and thrown away. Insect pests often winter over in the soil and plant debris – like dead leaves – around the plants and are ready to re-infest your plants when the weather warms up.

I read a book from the series by Ellis Peters called Brother Cadfael about a 12^th century English monk who solves mysteries using plants. It is a fun read if you are botanically inclined and like historical fiction. One of the ideas I retained from his musings is to leave the roots in the soil when you clean up a garden. This is especially good advice in my heavy clay where I am trying to get more organic materials into the soil. So I cut off my annuals rather than digging them up. In the spring, I plant around the old roots and let them continue to break down.

I think the vegetable garden should be the space that gets the most attention. Plant debris from veggies should be thrown away, not composted. This may be contrary to composters’ point of view, but a clean veggie garden makes for a healthier space next season. By all means, add more organic materials to the soil - till in tree leaves or add well-aged compost. But don’t use your vegetable waste here.

It is a common practice to plant tomatoes in different locations every year so that diseases from previous years don’t infect your new plants. So I am careful to pull up my tomato plants to remove the majority of the roots.

In the rest of the garden, I am less meticulous; although I always clean up as well as I can when there are obvious problems. It is harder to prevent overwintering pests in flower beds where there is a mulch, but it is still worth the effort to remove plant debris.

I mentioned that I gradually cut back the stems. This is on my perennials. As the plants go into winter dormancy, they store the food that their leaves are making in their roots; or stems and roots for trees and shrubs. Like hibernating bears, storing this food makes it possible to survive the winter and resprout in the spring. By cutting off green leaves and stems that are still photosynthesizing (making food using the sun), you are decreasing the food storage capacity of the plants. This is the same reasoning behind letting your tulips and daffodil leaves go completely brown in the spring before cutting them off.

I also leave stubble in my flower beds, unlike my vegetable garden. I cut stems 5”-10” above the ground on everything that isn’t diseased. The stubble acts as a miniature snow fence. Our snow is often melted on our wonderful sunny days but I want to keep as much as I can around the plants. These stems slow the melting by casting a bit of shade. They also slow down snow movement if there is wind and keeps the snow around the base of the plant.

Snow acts as an insulator and helps keep the soil at a constant cold temperature, which is good for the plant roots. A spell of a few weeks of sunny weather can warm the soil and fool the plants into new growth, even though it is still winter.

I don’t cut my ornamental grasses back until spring. I love having something to look at in my garden through the dark days and the grasses provide great winter interest. I have 8 different species in my small garden, 8 different seed heads and growth patterns to look at.

 

My process of gradually cutting back the garden may not work for everyone, but I believe it makes for stronger growth in the spring. Leaving stems means I have to cut back the dead stems again in the early spring, but I am out there anyway, cutting back the grasses. This helps me scratch the itch of needing to garden, even when there will be several more weeks of freezing nights.

Fall garden problems: powdery mildew

As fall sets in, a light frost may kill the leaves of cucumbers, squash and, more importantly at this time of year, your pumpkins. But the stems often suffer only minor damaged and can continue to support growing fruit until a severe frost. 

The blackened leaves are discouraging and if you decide to remove them, it's best to throw them away, instead of putting them in the compost. They often have a disease called powdery mildew.

Powdery mildew on a pumpkin plant. You can see that the new leaves aren't infected yet.

Powdery mildew frequently grows on these kind of plants. It looks like white powdery spots on the leaves and is often attributed to moisture on the leaves from overhead watering or high humidity. It's caused by several different species of fungi and is spread by splashing water or wind moving the spores around.
 

When the powdery mildew is advanced on a squash or pumpkin, the leaves have white mottling all over, they're distorted and curled, and the plant starts to turn yellow, then brown.

This is an infected leaf, with discoloration and curling at the edges.

I grew gourds and small pumpkins up my trellis and only watered them with drip irrigating. I'd hoped that this treatment would prevent powdery mildew since the plants were mostly off the ground. But even in their hot location, in an area that had been covered in gravel before my soil improvements, powdery mildew made a strong appearance.

Dead and dying leaves on my trellis. The bring green leaves are grape plants and they are uninfected so far.

It can affect many species of plants including perennials, and can be controlled with various fungicides. I consider fungicides a particularly virulent type of pesticide and would recommend using it very little or not at all. If we lived in high humidity or if you are growing commercial crops, they have their place, but not in a home garden. In early days of summer, diluted milk can be applied when the first spots occur, but when the disease is well-advanced, this treatment is apparently less effective.

Prevention is a better technique. This means removing and throwing away any plant parts and plant debris from around the affected plant, especially in the fall when you clean up your garden. This won’t completely remove the fungi from your garden, but it will certainly help!