Ironically, about half of my garden chores this month will involve work indoors as I prepare for winter.
Plant garlic - This is top of the list because if the conditions haven't been right for planting it in September, I'll plant it on Oct. 1. There's no magic to that date, it's a mental cutoff to prevent myself from delaying their planting too long, which easily happens when you work full-time.
Replace broken grow lights - I try to limit the number of plants overwintering indoors because I have only one south-facing window and it's in a spot where everything there would get knocked over. Instead, I'll use grow lights to support the plants that don't fare well in my low-light house. Unfortunately, something fried most of my grow lights this year, so they'll need to be replaced before things move indoors.
Making room for houseplants - In other words, housework. It's been months since my houseplants were moved outdoors for the summer, and new things have taken over their winter spots. Time to tidy up so they can go back indoors until next spring.
Flood the ants out of plants - This is different than ants in your pants, but still a pain that I had to learn the hard way. Before bringing plants inside, some measure needs to be taken to remove ants. They're there even if not obvious. My favorite technique is to put the flowerpots in a bucket with water up to the same level as the soil line in the pot and let them sit for about 48 hours. This will flood the tunnels and force the ants out. It takes a few days to do correctly, so it's an earlier in the month chore. Move plants inside and keep them there to avoid re-infestation. If this isn't done and frost sneaks up on me, I'll do it in the garage. Otherwise, the patio is the perfect spot for this task. I tried it in the bathtub once and won't make that mistake twice!
Pack up the watering timer and hoses - By October, routine drip irrigation isn't necessary, so I'll pack up the watering timer and all but one hose. Check out the section "What I'm NOT doing" (below) for questions about drip irrigation lines.
Raking and composting leaves - This will be a task mostly for later in the month, or even next month, depending on the timing of the first freeze. I've decided that I'll keep leaf mold completely separate from my other compost this year after reading that it is a good alternative to peat moss or coir in homemade potting soil.
Building new beds and planting areas - In central Oklahoma, the weather will still be above freezing except for the first frost sometime around Halloween. As a result, I can continue working on new beds. In fact, October is one of my favorite times to do this because the weather is cool enough to keep me cool while working but not so cool that outerwear is needed. Work on my much-delayed rain garden will be a focus this month.
Wrap maple trees - Soft barked trees like maples are prone to a problem called Southwest injury. This what causes bark to break open on the southwest-facing side of trees and is caused when air temps have frozen the sap but the sun heats it causing it to expand. A healthy, established tree shouldn't need this but young ones definitely do. Even though my tree is large, I'll still wrap it to prevent its southwest injury wounds from getting worse.
Get the frost blankets ready - I posted about this last week, and they are already out of the attic, but when frost finally makes it's way into the forecast, I'll evaluate which plants will need cover and find the appropriately-sized frost blanket.
Harvest, harvest, harvest - A lot of my warm season vegetables are producing again, because the excruciating heat has relented. Fall planted green beans are coming into full swing too.
Fall tomato care - My beefsteak tomatoes have set a quite a bit of fruit and with a frost just around the corner, it's time to start pinching buds. This will signal the plant to put it's energy and nutrients into the existing fruit instead of overworking itself by trying to make more. I'll be careful to keep them pruned as signs of fungal issues (typical) have started showing up.
A few things I'm NOT doing
Removing spent plants, limbs, or similar debris - Many favorable overwintering insects like native bees and butterflies have already settled in at this point. My philosophy is that if it was important enough to clean, I should have done it sooner. Anything left now waits until spring. Plants that succumb to the first frost will be removed just after the frost so they don't become home to overwintering beneficials or become a safe harbor for overwintering disease.
Pulling my drip lines - I think you're supposed to pack up drip lines and do all sorts of care to them this time of year. My system connects to hoses which lead to the various drip-line labyrinths around my yard. The hoses get packed away but the drip lines aren't taken up because it would disturb cool-season crops. I'll re-purpose some plastic bags to tape around the ends of the hose connections to prevent insects from overwintering in them, but that's the extent of maintenance I'll do.
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