Daniel Island's Master Gardeners offer harvest of ideas for fall!

It’s time to prepare our lawns for fall and one wonders when does that elusive season begin in the Lowcountry?

Don’t look at the calendar because it’s all about when the temperatures start to cool down, such as when daytime temps are in the 70s. Before you get started, you need to know what kind of warm season grass you have. Most of us on Daniel Island will have Centipede, St. Augustine or Zoysia.

Why is knowing your turf type so important?

When our daytime temperatures drop, it’s time to prepare turf for dormancy. Dormancy is when our warm season grasses turn brown. Grass needs to rest! It’s been a long, hot growing season. First, stop fertilizing your grass (that includes “Weed ‘n Feed-type” products). Fertilizing in the fall is like giving a child a candy bar before bed! Your grass needs some “quiet time” to adjust before winter.

Next, reduce irrigation. Grass going into dormancy needs less water. When you do water, remember to do so only in the early morning hours. It’s also a good idea to lower the mowing height. The exact desired height depends on your grass type (reason #1). A shorter lawn that is less wet decreases the chance of diseases that grow in cooler temperatures, like large spot fungus.

Fall is an excellent time to do a soil test. The results include your soil pH and what nutrients are present, as well as helpful recommendations. Making sure you know your turf type (reason #2) when you submit your sample assures your test recommendations are meaningful. The soil pH is important because the availability of nutrients is dependent on pH. Lime is used to increase the pH or “sweeten the soil” and sulfur is used to decrease the pH. The target pH varies depending on your grass type (reason #3). Adjusting the soil pH takes about 3-4 months, so autumn is the perfect time to prepare your soil for next spring.

What else can we do in fall? Tackle weeds that are just seeds. Put down pre-emergent herbicides before the cool season winter weeds germinate! The chemicals used are usually granular and should be applied uniformly with a spreader. It’s important to “water-in” pre-emergents, applying the volume of water directed. Consider a second application a couple of months later. Fall is also a good time to spot treat your lawn with post-emergent herbicides targeted at existing weeds. The cooler temperatures will improve the turf grass tolerance to herbicides. Also, perennial weeds and many annual weeds will be actively growing, making them easier to control.

Different herbicides are recommended for different grass types (reason #4) to avoid damaging healthy turf. Read the label on the product to determine which weeds are controlled and on which grass type the product can be used. As always, use lawn herbicides with caution. They are harmful chemicals. The label is the law!

Soil samples can be submitted to the Daniel Island Library “Ask a Master Gardener” table, on the first Monday of the month (if there’s not a holiday) from 4 to 6 p.m. Good luck!


1. What kind of warm season grass do you have? Centipede, St. Augustine or Zoysia?

2. Prepare for dormancy:

- Do not fertilize (that also means do not use Weed ‘N Feed)! Let your lawn get ready to rest.

- Reduce irrigation. Only water early in the morning.

- Lower mowing height.

- A shorter lawn that is less wet decreases the chance of diseases that thrive in cooler temperatures to grow (like large spot fungus).

3. Do a soil test to determine pH and nutrients present

- May need to add lime or sulfur (takes 3-4 months to adjust the pH)

- Nutrient availability in the soil is dependent on pH

4. Weeds

- Treat with pre-emergent herbicides when daytime temps are in the 70s before cool season winter weeds germinate

- Pre-emergents herbicides are usually granular, applied uniformly with a spreader and need to be watered-in. After application, consider a second application and spot treat existing weeds with targeted post-emergent herbicides.


- Determine which weeds are controlled and on which grasses the product can be used

- Use only the recommended amount

- The cooler temperatures will improve the turf grass tolerance to herbicides

- Use with caution! These are harmful chemicals

For more information: Visit the Clemson Home & Garden Information Center website at www.hgic.clemson.edu.

Fall garden check list:


-Divide and replant spring and summer plants. Examples: Daylilies, Agapanthus, Rudbeckia, and Echinacea.

-Take cuttings to start new plants indoors. Use Rootone to help establish the new plant roots. Examples: Hibiscus, Butterfly Bush, Mandevilla.

-Dig up bulbs, dry and store for winter

-Cut back Chrysanthemums after blooming


-Lightly prune to improve shape and appearance (you don’t want to promote new growth before winter).

-Prune roses after blooming

-Check Camellias and Hollies for scale (HGIC 2012)



-Cold weather bedding plants – winter annuals

-Shrubs – Hollytone 4-3-3 for acid-loving shrubs, such as Hollies, Azaleas, Camillias, Evergreens, Hydrangeas and all-purpose 12-4-8 (nitrogen-phosphorus-potassium) for others.


-Trees and shrubs (HGIC 1000)

-Bulbs (December)

-Roses (December)

-Ivy (December) use hair pins to hold down runners


-Remove annuals that have bloomed out

-Get soil samples tested from lawn and beds (HGIC 1652)

-Rake leaves and add to compost pile

-Mulch plants to prepare for first frost

-Move porch plants inside before the first frost

-Make sure new plantings get watered

-Cut back length of time for water on irrigation system

-Fill bird feeders

-Purchase frost cloths/blankets to protect tender plants from freezing temperatures – example Remay.

-Use small Christmas lights under frost blankets to provide added warmth around plants during freezing temperatures.

(Source: Clemson University Cooperative Extension/Home & Garden Information Center – www.HGIC.clemson.edu)

Daniel Island Publishing

225 Seven Farms Drive
Unit 108
Daniel Island, SC 29492 

Office Number: 843-856-1999
Fax Number: 843-856-8555


Breaking News Alerts

To sign up for breaking news email alerts, Click on the email address below and put "email alerts" in the subject line: sdetar@thedanielislandnews.com

Comment Here