Gardening Guides
Southern California Gardener's September Checklist
Before prime planting time, clean out the old garden, prepare for the new, and dream up ideas for fall flowers and veggies
September in Southern California is a transition from summer back to springlike weather — warm days, crisp nights and a chance of hot, dry Santa Ana winds. Over the next few months, we'll see the shift at local nurseries from summer bloomers to winter flowering plants and from warm season veggies to cool season varieties.
While October is prime planting season, September is best spent cleaning out the old, preparing the soil and planning your fall garden.
This month look for fall-planted, spring-blooming bulbs, including daffodils, narcissus, tulips, hyacinth, bearded iris, crocus, allium, ixia and lilies. Stock up on seeds of cool season veggies and annuals — such as sweet peas, nasturtium and wildflowers — so you're ready to get them in the ground as soon as the heat subsides. You'll also want to hit the books, catalogs and Internet for ideas.
First, check out these tips, and happy September digging!
While October is prime planting season, September is best spent cleaning out the old, preparing the soil and planning your fall garden.
This month look for fall-planted, spring-blooming bulbs, including daffodils, narcissus, tulips, hyacinth, bearded iris, crocus, allium, ixia and lilies. Stock up on seeds of cool season veggies and annuals — such as sweet peas, nasturtium and wildflowers — so you're ready to get them in the ground as soon as the heat subsides. You'll also want to hit the books, catalogs and Internet for ideas.
First, check out these tips, and happy September digging!
Adding nutrients: Now's the time to add nutrients to the beds you plan to plant when the weather cools. Compost existing beds. For new beds, add compost, N-P-K (see below), trace elements and gypsum (for sticky clay soils) and turn it all in.
Bed preparation: I like to add three to four inches of organic material, such as compost or planting mix first. For heavy, sticky clay soil, add some agricultural gypsum at this point to help break it up. Scatter slow-acting, low concentrate N-P-K and trace nutrients on top and then give it all a good mix with a rototiller or a shovel. Compost made of mixed materials such as green waste, egg shells, coffee grounds and other kitchen waste generally contains all the necessary nutrients for healthy growth. If you don't happen to have yummy homemade compost, add individual ingredients to your mix, following label directions. You have lots of options; here are just a few to cover the N-P-K:
Bed preparation: I like to add three to four inches of organic material, such as compost or planting mix first. For heavy, sticky clay soil, add some agricultural gypsum at this point to help break it up. Scatter slow-acting, low concentrate N-P-K and trace nutrients on top and then give it all a good mix with a rototiller or a shovel. Compost made of mixed materials such as green waste, egg shells, coffee grounds and other kitchen waste generally contains all the necessary nutrients for healthy growth. If you don't happen to have yummy homemade compost, add individual ingredients to your mix, following label directions. You have lots of options; here are just a few to cover the N-P-K:
- For nitrogen ("N"): bloodmeal, cottonseed meal, or well-composted manure
- For phosporus ("P"): bone meal
- For potassium ("K"): kelp meal, wood ash
Select Cool Season Veggies
Plant cool season vegetables — primarily those grown for their leaf, root or tender seed pods — toward the end of September in Southern California.
Plant cool season vegetables — primarily those grown for their leaf, root or tender seed pods — toward the end of September in Southern California.
Peas, please. Time to plant peas, too: snow, snap and English. Keep in mind that English peas need to be shelled; the other two are eaten pods and all.
Cool-season Crops to Grow in Fall
Cool-season Crops to Grow in Fall
Cool season flowers. Look for these to sow this month once things cool down: 'Bachelor Buttons', calendula, black-eyed susan, coreopsis, wildflowers, nasturtium and sweet peas. Plant "early flowering" varieties of sweet peas now, and you'll have them by December.
Outdoor Garden Trellis
Add trellises now for winter structure and color. For your climbing veggies and flowers, spice it up this year and go for something colorful and striking.
Divide bulbs. It's time to dig up and divide 'Naked Ladies' (Amaryllis) and other fall bulbs that have become crowded. Lift, divide and replant after the bloom is done but before the leaves appear.
Plant fall bulbs. Look for daffodils, anemone, ixia, dahlia (LOVE the dinner plate dahlias), calla lilies, iris, babiana, watsonia, freesias, ranunculus, muscari and lilies. Get them in the ground as soon as they arrive at your local nursery or via mail order.
6 Unsung Bulbs for Fall Planting
6 Unsung Bulbs for Fall Planting
Try some chemistry in the garden. If you're up for a little horticultural fun this month, try messing with the color of your hydrangeas. Start now before new buds develop, altering soil chemistry to enhance the blue in the blooms of pink- and blue-flowering varieties. (The trick doesn't work with white-bloomed varieties.)
You can modify the color of hydrangea flower heads (which are actually bracts) by changing the pH of the soil. For blue flowers, you'll want to achieve a pH of 4.5 to 5.5. For pink flowers, you want a pH of 7.0 to 7.5. Use an inexpensive soil pH test kit from the nursery or hardware store to test the pH of the soil around the plant's roots. Lower the soil pH by adding sulphur or aluminum sulfate (making the soil more acid). Raise the soil pH by adding ground agricultural limestone (making the soil more alkaline). Follow label directions for application rate and frequency.
Water citrus. Water citrus trees deeply and uniformly while the heat is still on. Dry roots result in split fruit.
Soil prep. A great garden begins with great soil: Don't skimp on this vital task. The goal of soil preparation and amendment is to create a healthy soil microbial suite — the microflora and microfauna that are essential to breaking down organic material that other soil flora and fauna convert to soluble plant nutrients. (Admittedly, this is an over-simplification of the process. The point is, be good to your soil, and it will be good to you.)
Soil prep will depend on what you're planting.
- Natives and Mediterranean plants. These need little soil prep. Most are adapted to lean soils (low organic content, low nutrients).
- Trees, shrubs and perennials. Limit soil amendment to the planting hole itself, and leave surrounding soil undisturbed. A heavy layer of mulch around the new plant and adjacent soil will provide what's needed for a healthy soil microbial suite.
- Annuals and vegetables. Prepare an entire area or bed to provide the organic-rich, well-draining soil that these plants require.
New beds: Let's assume you're just getting started and you want to have beds ready for planting now. To prepare a new bed, remove unwanted plant material (weeds, sod, etc.), turn the soil and water thoroughly. Continue watering for at least two weeks, allowing weed seeds to germinate. Yank those weed-lets and you're ready to proceed.How to Win the Weed War