Fertilizer FAQs

Fertilize new lawns after planting grass seed using a starter fertilizer. High-quality lawn fertilizer gives turf essential nutrients that help it grow thick. As your lawn matures, you will want to continue with a proper fertilizing schedule, but that can depend upon what type of grass you have. Learn more about when to fertilize your lawn here. 

Do not apply weed and feed or herbicide products when planting a new lawn, even if they are selective. Weed killing products can prevent grass seeds from germinating so wait until your lawn is established. Lawns usually take about one year to be fully established and benefit from weed treatments. To learn how to fight difficult weeds learn more here. 

How often to fertilize your lawn will depend on what type of grass you have. Cool-season grasses should be fertilized a total of three times. Twice in the fall in September and November, then again in the spring in May or April after the first flush of growth.

Warm-season grasses should be fed three times during active growth periods, but not during the hot midsummer months. Apply the fertilizer in three phases: first when the grass starts to green in early spring, next in late spring, and once again in late summer.

When to fertilize your lawn will depend on what type of grass you have, warm- or cool-season. For cool-season lawns, the best time to fertilize is in the fall so that they are well fed prior to winter. Warm-season grasses should be fertilized in early spring. 

There are many things a homeowner should do throughout the year to maintain a healthy lawn. That can include fertilizing, mowing, applying herbicides and treating for disease and pests. 

The proper schedule for caring for your lawn so that larger issues don't arise will depend on whether you have a cool-season or warm-season lawn. Check out our cool-season lawn care calendar orwarm-season lawn care calendar to learn how to care for your lawn. 

When Ironite is applied according to the label, we would not expect the product to harm pets. However, we recommend keeping all people and pets off of the treated area until it has dried. Once it is dry pets can reenter. 

Apply Ironite Mineral Supplement 1-0-1 when your lawn starts to lose its green color, which may be due to iron deficiency or the stress of hot summer months. Ironite is non-burning and greens up lawns without the growth surge that requires excessive mowing. To learn more about the benefits of applying Ironite, visit our article on how to maintain a green lawn. 

When applied according to the label, we would not expect the fertilizer to harm pets. Depending on the formula, do not let pets enter the are until dust has settled or product is watered in and treated area is dry. We also recommend keeping all pets off of the treated area for at least 24 hours. 

Unless the product specifically states it can be used on pastures it should not be applied. 

Pets can return to an area treated with most fertilizers once the treated location is dry or dust has settled. Weed and feed fertilizers are an exception; pets should be kept out of the treated area for 48 hours. If you think your pet has been exposed and is having an adverse reaction please call our customer care number immediately at 1-800-265-0761. 

Plants need nitrogen, phosphorus and potassium (NPK) which are 3 of the 17 nutrients essential to all plant life. The necessary NPK ratio can vary depending on the type of plant you are fertilizing, which you will usually see listed prominently on the packaging. While some all purpose fertilizers can be used on many different plant types, it is not advisable to use fertilizer on any plants that are not listed on the label. To learn more about what these ratios mean, visit our article "Numbers to Grow By: Understanding Fertilizer Labels."

Because fertilizers have different NPK ratios you will want to make sure to apply the appropriate fertilizer for the type of plants you are growing. Since application rates can vary, be sure to follow the directions for the fertilizer you have. To see a list of our plant fertilizers, click here. 

The best time to apply lawn fertilizer is when weather is moderate. We don't recommend applying product when a frost is expected or if plants are stressed due to heat or drought. Otherwise, products can be applied during the early morning or early evening hours before or after the heat of the day.

Fertilizer should be applied to dry lawns with the exception of weed and feed products. Water your lawn prior to applying weed and feed for best results. However, always be sure to follow the directions on the label for use as products may vary. See all of our lawn fertilizers here. 

To get a deep green lawn apply Ironite Mineral Supplement 1-0-1. With mild iron deficiencies, lawns will yellow, but with severe iron chlorosis, turfgrass can die. Ironite contains iron and beneficial microbes, which will turn yellow lawns green without excessive growth or burning. Ironite is also ideal for yellow lawns during summer months. To learn more about how to get, and keep, a healthy lawn visit our article "Greening Up Your Lawn." 

The best time to apply lime is in fall and spring. Fall has an added advantage, as rain, snow and cycles of freezing and thawing help lime break down and begin to work. First, test your soil to learn your soil's starting pH. Based on your soil's pH, apply the appropriate amount of lime to get your soil to the ideal range between 6.8 and 7.2.

Lime helps balance soil pH, which can change soil conditions so it does not promote moss and weeds.

To find out how much lime to apply to your lawn, you will need to start with a soil test. A soil test will give you your soil's pH to ensure that you are applying the correct amount of Pennington Fast Acting lime to correct the problem. The ideal pH for lawns is between 6.8 and 7.2. For more about application rates please visit our Fast Acting Lime product page.

Pennington Fast Acting Lime includes Advanced Soil Technology (AST), which contains polymers that are impregnated into and coated onto the specially engineered granules. AST is continuously released into the soil as moisture is applied to the granules. Additionally, one 30 LB bag of Pennington Fast Acting Lime is equivalent to five 30 LB bags of regular pelletized lime. 

Popular forms of organic lawncare such as pulling , burning, boiling water, salting or vinegar will damage your grass. The best way to fight weeds, if you are adverse to using fertilizer, is to make sure you have healthy soil by taking a soil sample and then adding amendments such as lime or gypsum. In addition to having healthy soil, make sure to overseed your lawn every fall to choke out weeds. Learn more about soil amendments here. 

To kill lawn weeds we would recommend using a weed and feed product. See our weed and feed products.

Our Alaska Fish Fertilizer 5-1-1 is an OMRI-listed (Organic Materials Review Institute) fertilizer so it can be used for organic food and crop production.

Apply gypsum in areas with compacted soil, such as areas composed with a lot of clay. Gypsum helps to loosen compacted soil, increases water penetration, promotes root growth and adds calcium without raising pH. It's also great for vegetable gardens with plants that have higher calcium needs, such as tomatoes.

We recommend avoiding applying fertilizer in such a way that the run-off could end up in fish ponds. Fish are very sensitive to chemicals, so use caution because fish could be harmed.

When Pennington products are applied according to the label, we would not expect them to harm wildlife. 

Amendments are added to soil to change and improve it. Unlike fertilizers, which add nutrients to soil, amendments modify the condition of the soil itself which provides a better environment for plant growth.

Fertilizers impact plant growth directly, while soil amendments affect growth indirectly and sometimes deliver nutrients as a bonus. Soil amendments aren't fertilizer substitutes. Instead, they help fertilizers do the job they're intended to do by getting tilth and other factors in order.

All seeds and fertilizers can require different spreader settings. We recommend that you refer to the manual of the spreader you wish to use for the correct spreader. 

Pennington Fertilizer products have a customer satisfaction guarantee in which, if a customer is not satisfied, we will refund the purchase price of the product as long as it is within 90 days of purchase and we receive the receipt.