Fall Lawn Prep

Mid-August to October

Fall Lawn Prep

Fall is the best time of year to fix a New England lawn — better than spring. Answer four questions and get your seed + feed kit, with the exact pounds for your yard.

1. What’s the job this fall?

This decides whether you need phosphorus or potassium — they are not interchangeable.

2. How much sun does that area get?

Measured in summer, when the trees are full.

3. Anything working against you?

Pick the biggest one.

4. Organic or conventional?

5. How big is the area?

A rough number is fine. Leave it blank and we’ll just show the rate.

square feet

Your fall kit

Why fall beats spring

The soil is still warm

Grass seed germinates on soil temperature, not air temperature. In late August the soil is still holding summer heat while the air has cooled off — that combination is close to ideal, and you don’t get it in spring.

The weeds have quit

Crabgrass and most summer annuals are finishing their life cycle. Seed you plant in spring competes with all of them. Seed you plant now doesn’t.

Roots get two seasons

Fall-planted grass roots through autumn, sits out the winter, then roots again in spring before summer stress arrives. Spring-planted grass gets one short run at it before July.

Three ways people wreck a fall lawn

Weed & feed on new seed

Pre-emergent herbicide cannot tell your grass seed from a weed seed. It stops both. If you are seeding, do not put down weed & feed or crabgrass preventer — wait until the new grass has been mowed three times.

A big nitrogen push in late fall

Nitrogen tells grass to grow leaves. Tender new leaves going into a hard freeze is how you get winter injury and snow mold. Late in the season the lawn wants potassium — it hardens the plant off. That is why a proper winterizer is high in K and light on everything else.

Feeding an acidic lawn

Most New England soil sits around pH 5.0–5.5. Grass wants 6.0–7.0. Below that, the nutrients are physically in the soil but the roots cannot take them up — you are fertilizing a lawn that cannot eat. If you have never limed, that is the first thing to fix, not the last.

On phosphorus: several states restrict phosphorus lawn fertilizer unless you are establishing new seed or a soil test shows a deficiency — new seeding is usually the exemption, which is exactly why the starter in your kit has phosphorus in it and the winterizer does not. Check your state’s rule before you spread.