Mulch protects your tomato plants while also improving their health and the eventual harvest. Mulching materials keep moisture in the soil by inhibiting evaporation. A mulch also suppresses weeds and helps maintain soil temperatures throughout the growing season. You can apply an organic mulch, such as straw, around tomatoes as soon after planting as possible. The straw keeps low-hanging tomatoes off the ground so that they remain clean and aren't fed upon by ground-dwelling pests.
Pull all weeds from the tomato bed prior to mulching. Grasp the weeds near their base, and pull them straight up to remove as much of their root systems as possible.
Spread a coarse mulch, such as seed-free straw, over the soil surface. Apply it at a 2-inch depth if the tomato seedlings are less than 6 inches tall. Build it up to a 3- to 4-inch depth as the plants grow. Avoid burying lower leaves along the stem beneath the mulching material.
Pull the mulch back from the tomato stems so that there is a 2-inch space between the mulch and plant stem. Mulch resting against the stem can cause rot or disease problems because of trapped moisture in the mulching material.
Water mulched tomato plants deeply once or twice a week to maintain the soil moisture beneath the mulch layer. Most moisture can seep through organic mulch with sufficient irrigation. Apply 1 to 2 inches of water per week to your tomatoes, or enough so that the top 6 inches of soil remains moist.
Things You Will Need
- Straw mulch
- Inorganic mulches such as black plastic can also prevent weeds and retain soil moisture while warming the soil earlier in spring. Apply these mulches before transplanting the tomatoes, then cut holes in the plastic for each plant. Red plastic can help speed tomato ripening.
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