A September garden checklist for beginner and professional gardeners working in the Pacific Northwest
Knowing where to start in the garden can be a completely overwhelming feeling. There's so many weeds! There's too much to do! The grass hasn't been cut in ages! Blackberries and buttercups are taking over my LIFEEEE!
If you look out into your garden and you get that sinking feeling that it may be turning into Grey Gardens, don't sweat! I've got your back with this easy-to-follow September garden maintenance checklist broken up into 7 key sections of your garden and yard:
General Garden Maintenance
Vegetable Garden Maintenance
Flower Garden Maintenance
Lawn Maintenance
Tree and Shrub Maintenance
Indoor Plant Maintenance
Miscellaneous Fall Maintenance
1. General Garden Maintenance
Clean-up: While there's still technically a few weeks of summer left, Labor Day, in the beginning of September, is the unofficial end of summer. And with the end of summer comes fall clean-up. Early-planted vegetables and flowers are either done fruiting and flowering or on their way out. Remove dead and dying annuals, weed, and do a general tidy of garden beds.
There's still many weeks (if not months) of growing for fall crops and perennials, but it's a smart idea to do a little garden tidying now instead of saving it all for later.
Water: September in the Pacific Northwest is still a very dry month in terms of precipitation. According to weatherspark.com, Seattle receives an average of 1.3 inches of precipitation during the month of September. Now, that's more than August, but on average, plants need about 1 inch of water per week! This means most plants are operating on a water deficit of nearly 3 inches during September! So don't put your hoses and sprinklers away yet. Remember to keep watering, especially on hot, sunny days.
Mulch: September is a great time of year to tidy up the garden and add a few inches of mulch or compost to all garden beds. Mulch reduces the ability of weed seeds in the soil to germinate and grow, thereby reducing weeds in your garden. Other benefits of mulching in September include protecting plant roots from cold and frost damage during the winter, protecting soil by reducing erosion during winter storms, and mulch/compost feeds soil microbes by adding a layer of rich organic material full of nutrients.
Mulching garden beds is incredibly important and beneficial to plants and soil microbes. In the Pacific Northwest, you can mulch garden beds any time of year due to the modest climate. However, September is a good time of year to mulch because the weather is still favorable and mulch will protect garden beds during fall and winter storms.
Fertilize: If you planting fall crops or your perennials are looking a bit tired, September is a good time to fertilize. Anytime you plant a new round of annual crops, you'll need to replenish the nutrient supply in the soil. Add a dash of your favorite fertilizer, rake into the soil, and plant. Remember to water plants in so roots can start growing and up-taking fertilizer immediately.
In the case of perennials, some will need a boost of fertilizer to continue growing for the next several weeks until temps cool and light levels decrease. I suggest adding a small amount of fertilizer for this boost--but be careful not to over-fertilize. You don't want to stimulate a ton of growth right before winter, as this can lead to long, lanky, and weak branches that break and become diseased during the winter.
Tool maintenance: If you've been too busy weeding, harvesting, and all around enjoying the summer garden to maintain your tools, now is a good time to catch up! Clean and sterilize all your tools with a diluted bleach solution, wipe clean, and allow tools to air dry. Sharpen tools that are used for cutting (pruners, sheers, loppers, hoes, shovels, etc.). And oil any moving parts on tools. Cleaning, sharpening, and oiling ensure you have a positive experience and extends the tool's lifespan.
2. Vegetable Garden Maintenance
Harvest: If you planted summer vegetable crops, those plants should be producing for at least another month or two. Remember to go out into the garden at least once a day to harvest zucchini, tomatoes, peppers, and other hot crops.
Plant cool-season crops: If you're not completely worn out from the summer garden rush, September is a great time to seed cool-season crops and get them established before light levels decrease and nights get cooler. Some easy-to-grow cool-season vegetable crops include lettuce, leafy greens, kale, chard, Brussels sprouts, radishes, turnips, onions, and leeks. If you have enough space and sunlight in your garden, you could be harvesting cool-season crops all winter long!
Plant garlic: If you're not a vampire, now's the time to plant garlic! Garlic should be planted September-October to have a harvest next summer. Simply plant cloves about 4 inches deep into the soil, fertilize, cover, water-in, mulch, and then let it grow. Garlic is incredibly easy to grow and with fall just around the corner, chances are you won't have to water it very often.
Compost: Composting is literally one of my favorite garden tasks. Why, you ask? Well, have you ever composted? It's an amazing process: toss all your kitchen scraps into a pile, cover it with garden scraps (leaves, grass clippings, even weeds), and then let the microbes and fungi turn all of that into compost! You may need to turn the pile to ensure all layers get an equal amount of decomposition, but it's one task you can basically sit back and let someone else (in this case, the soil critters) do the work. I love any garden task where I don't have to do the bulk of the work.
3. Flower Garden Maintenance
Deadhead: All the best summer flowers are still going strong. Remember to continue to deadhead and harvest flowers so the plant will continue flowering. To deadhead, either prune off the spent flower or cut lower on the stem just above the first set of leaves. Either way works, choose your preference.
On the other hand, if you're growing flowers for seeds, leave a few spent flowers intact and wait until the little seeds inside brown and become hard. Then cut off the flower head, separate seeds from stems and petals, let the seeds air dry, and then store the seeds in a dry container for next season.
Divide perennials: If you've been successful this summer and your herbaceous perennials have multiplied (perennial sunflowers, daisies, hardy geraniums, autumn joy sedums, hellebores, hostas, etc.), consider dividing and transplanting. Take your shovel and spear the plant right down the middle as if you were cutting a tray of brownies in half. Continue cutting around one side of the plant with the shovel, inching the tip of the shovel further under the plant roots (about 4-6 inches depending on plant type). This will dislodge roots and make it easier to pick up this half of the plant. Move the dislodged plant to a new part of the garden and transplant it immediately. Backfill the hole (left behind after dividing) with soil and cover it with compost. Easy!
Plant spring bulbs and corms: In the Pacific Northwest, you can plant spring bulbs and corms from September through January (or up until the ground gets too hard and frozen to plant). But I prefer planting bulbs and corms in September and October, as the weather is still nice and it's fun to get a jump-start on next season's garden.
No need to fertilize when planting bulbs and corms, but you could fertilize next spring when leaves start emerging.
Make sure you plant bulbs and corms deep enough so that soil protects them during the cold, winter months. And if you have had issues with squirrels and other rodents digging up and eating bulbs in the past, try sprinkling cayenne pepper around fresh plantings. Rodents HATE spicy things and will be reluctant to mess with anything around cayenne pepper.
4. Lawn Maintenance
I don't talk a whole lot about lawn and grass maintenance here, but I do realize that most people have lawns and your garden will look even better when it's complemented by a healthy, green lawn. September is a good time to do a little extra lawn maintenance, now that it's a little cooler and rainier. You should continue to mow your lawn every few weeks, and here are a few other lawn maintenance tasks:
Aerate: to increase drainage
Overseed: to replenish grass that may have died during the summer heat
Fertilize: just a little to ensure greener grass
5. Tree and Shrub Maintenance
Harvest: Harvest apples, pears, and late-season berries (yum!!).
Prune: Prune any dead, damaged, and diseased branches from trees. Refrain from any large-scale pruning, as this can promote new growth, which will be more susceptible to damage during the winter.
Flowering shrubs can be lightly pruned to remove spent flowers. Alternatively, leave spent flowers on the shrub to dry and provide winter forage for birds.
Plant: September is a great time to plant trees. Labor Day and fall sales are a great time of year to make bigger purchases such as trees. Make sure to transplant trees immediately after purchase to ensure the most time possible for root establishment before winter.
Water: Deeply water any newly planted tree to promote root establishment and enable nutrient uptake. Additionally, if established trees and shrubs are looking a bit tired after a dry and hot summer, consider watering at least once a week until the rains start again.
6. Indoor Plant Maintenance
I'll be the first to admit that I'm not great at growing indoor plants, but a lot of you are! If you brought plants outside for the summer, September is when you should start considering moving them back inside. Early September is still warm and sunny, but the fall equinox marks the turn in seasons with cooler, damper nights--which could decimate sensitive indoor plants. To ensure you don't kill your plant babies:
Move indoors: Bring houseplants and tender perennials (like zonal geraniums) that spent the summer outside inside before nighttime temperatures drop.
Check for pests: Inspect plants for pests (such as aphids, slugs, and mites) before bringing them inside. If you find any pests, remove immediately and spray the plant with Neem Oil.
Reduce watering: As days get shorter, reduce watering of houseplants and tender perennials to match their slower winter growth rate.
7. Miscellaneous Fall Maintenance
Prepare for frost: Keep a close eye on the weather, especially after the fall equinox, as temperatures can drop quickly and become life-threatening to unprotected plants. When temperatures start dipping in the 40s and below at night, consider covering plants (such as your cool season annual crops) with protective coverings. I prefer Remay, but any fleece cloth with work. If you're in a pinch, you can use an old flat sheet to protect plants and help with cold acclimation.
Clean up equipment, tools, hoses, etc.: Clean up tools and equipment left outside during the summer. Storing tools and equipment inside during the winter months will prolong the lifetime of the item and make the garden look tidy during the off-season.
Plan for next season: Take a moment to be a little introspective and write down what worked this year, what didn't work so well, if you had any pest problems, or if a new part of the garden is especially sunnier or shadier now. Writing all this down will help you plan for next year's garden and may help in deciding what new and different techniques or crops to try.
Plant cover crop: September is the perfect time to plant cover crops in bare beds. Never leave soil bare all winter long, as vital nutrients and organic matter will be swept away during winter rain storms. Cover crops are low maintenance, winter-hardy, will provide soil cover, and add much-needed nitrogen to the soil. Some of my favorite cover crops are red clover, broad beans, and winter rye grass.
Summary
There's a ton of things to do in the garden before the "big dark" sets in here in the Pacific Northwest. Try to check off a few things each day to ensure you and your garden are ready for winter. Key areas of the garden include:
General Garden Maintenance
Vegetable Garden Maintenance
Flower Garden Maintenance
Lawn Maintenance
Tree and Shrub Maintenance
Indoor Plant Maintenance
Miscellaneous Fall Maintenance
What do you like to focus on during the month of September?
Comments