Guide to the Best Mulch for Strawberries and How to Apply It

Ava Wilson

By Ava Wilson

07 Jan. 2025

8 min read

Best mulch for strawberries
Photo: @goodplanetnz

Table of Content

    Mulching is a crucial aspect of the strawberry plant, particularly in terms of sudden temperature changes from season to season. Heavy straw mulch applied in late fall or early winter protects their roots and crowns from freeze-ups. The straw cover stabilized soil conditions, even freeze-thaw action cannot dislodge the plants from the soil.

    Timing for Mulching

    Timing is the essence of mulching. It should be done at least after the first hard frost, but more ideally after soil temperatures have cooled down to around 40°F (4°C). Even small exposures to frost encourage higher summer yields. Timing will vary by climate zone, but general guidelines suggest waiting until the foliage turns red or laying flat plants having been exposed to a few freezing temperatures and ready for some winter protection.

    Early Mulching Dangers

    Strawberry plants mulched early in the season face risks from root and crown rot by late autumn, particularly if the weather has become wet. This risk can be avoided by applying straw mulch once leaf debris is indicated on the plant. This way, the plant's energy is no longer required to sustain its above-ground portions.

    Mulching With Straw at the Close of Fall

    Mulching With Straw
    Photo: @gardenboxnz

    Apply straw mulch on the strawberry plants in late fall to shelter them from damage that winter causes. Mulching prevents drying and shields the plants from extreme cold. Besides this, it retains the moisture of the soil, which subsequently helps the plants in spring and summer.

    Hazards of Exposure to Strawberries

    Leaving strawberry plants uncovered over winter is damaging through crown damage and sometimes causing death if the temperature does reach as low as 12°F. Mulching is a must in regions with severe winter conditions.

    When to Mulch

    For best cover, mulch when the soil temperatures stay at or below 40°F for three days in a row. This means the plants have stopped growing as the winter has set in. In colder climates, this happens around late November or early December. Wait until plants are passive for proper insulation.

    Rate and Application of Mulching

    For uniform distribution, apply 2.5 to 3 tons of straw per acre in a 2 to 3-inch layer on top of the plants. Smaller farms often apply straw by hand. However, larger farms will use mechanical mulchers to fluff and spread straw uniformly down the row.

    Time Application Around Early Snowfall and Cold

    Early snowfalls and cold, which include some late October, can also disrupt mulch timing. Snow alone offers some degree of insulation, so do not rush out to apply mulch the first time snow hits. Wait instead for the soil temperatures to settle below 40°F and plants are hard asleep. The exception is that early fall snow melts and creates a window for mulch application ahead of the arrival of steady cold.

    Best Mulch Materials

    Other useful mulching materials for strawberries include clean, weed-free oats, wheat or soybean straw, or even chopped corn stalks. Spread these at a depth of 3–5 inches to settle organically to 2–4 inches. That depth offers the best protection without damaging plant growth.

    Straw Mulch Management for Strawberries Plants

    Straw Mulch for Strawberries
    Photo: @jimmysicecreams

    Facing High Winds

    The mulch may be tied down by using boards or wire fencing, which can also be weighed down with bricks in windy locations. This will keep the straw from blowing away and hold it down evenly.

    Do Not Use Leaves as Mulch

    Leaves are not a good straw mulch material because they will mat together, create air pockets inside, and layer which ice formation can penetrate and prevent adequate insulation with excess moisture damage in plants.

    Timely Removal of Mulch

    There should not be any disturbance of straw mulch left on strawberry plants until new growth starts to happen during spring. A heavy straw mulch left on too early, such as in March, may encourage premature blooming. The early blooms are susceptible to frost damage, which would reduce yields.

    Inspection for Mulch Removal

    Monitor under the mulch periodically on warm spring days for the date to strip it off. Once about 25 percent of the plants show signs of new growth, pull off the mulch. In central Iowa, this is about mid-April.

    Protecting Against Late Season Frost

    If a killing frost is predicted at the end of the season, gently rake the mulch back over the plants to shield them from the approaching freezing weather. This gives an added extra layer when damage occurs during bloom.

    Straw Removal in Spring

    Remove straw in spring when soil temperatures at a 4-inch depth average about 40°F. Remove most of the straw from the top of the row, retaining just enough to suppress weeds and keep berries off the ground. Straw left beside the rows provides an easy spot for pickers to stand so the soil doesn't splash onto the berries.

    Rewarding Effort

    Though mulching is a job that is hard, it certainly has rewarding yields. In fact, proper mulching at the ground will definitely allow you to enjoy a strawberry harvest, ripe and ready for many delights.

    Table of Content

      Related Stories