Soil health is of vital importance in growing vegetables successfully. Conducting soil tests and adding organic matter or fertilizers are both great places to start in order to create an ideal garden space.
The primary nutrients for plant nutrition include nitrogen (N), phosphorus (P), and potassium (K). Use only what your soil test indicates as necessary; overdoing it could result in imbalanced nutrition for vegetables.
Spring
Fertilizers provide essential nutrients necessary for healthy vegetable and flower gardens, providing maximum exposure and water. Fertilizers help increase yield, improve plant vigor and resistance against diseases and insects as well as supporting strong root systems. Knowing when, how much and which fertilizers to apply is paramount to crop success.
For edible crops, spring is the best time to fertilize. Mixing fertilizer into the soil before planting helps ensure that seedlings and transplants get off to an excellent start. If your seeds or transplants have already been planted, lightly work in some fertilizer into the top 3 to 5 inches of your beds so as not to disturb young roots.
Most gardeners rely on an generalized fertilizer schedule for fertilization purposes; however, soil testing provides the most precise way to know when and how much to apply. You can purchase kits from hardware stores or submit a sample to university extension laboratories; either way the results provide a starting point for adding nutrients based on recommendations – you could choose specific mix of nitrogen, phosphorous and potassium or an all-purpose one that covers most vegetables well.
Fertilizer labels typically indicate their nitrogen, phosphorous, and potassium contents in this order. Some vegetables such as leafy greens require higher nitrogen levels while beans and peas thrive with more phosphorous and potassium content. Starting off strong can encourage healthy growth but as time progresses and fruits form it is wiser to switch to lower nitrogen products as the season continues.
Vegetable plants typically receive all of their nitrogen needs from organic matter such as decomposing manure or compost, although an occasional side-dressing of nitrogen may be required if weeds start pulling up important nutrients from vegetable beds. A low-nitrogen fertilizer such as ammonium sulfate (21-0-0-24) should be sprinkled lightly around outer edges of vegetable beds where weeds begin choking out plants.
Summer
As plants mature and expand in size, their nutritional needs increase and should be met through regular fertilization. Vegetables like summer squash, beans, corn, and tomatoes benefit from receiving midsummer applications of an organic balanced fertilizer with an NPK ratio of 3-1-2 or greater; high amounts of chemicals found in liquid or granular products could harm both their roots and foliage, damaging young plants further.
Before applying any type of fertilizer to the soil, it’s crucial that you gain a solid understanding of its pH levels and essential nutrient levels. A soil test performed either at home with a kit or through sending samples directly to your local Cooperative Extension office can provide this insight and allow you to select an ideal fertilizer and adjust its application rate to best meet the needs of your garden.
Fertilizing in the summer helps ensure a prosperous harvest. As the season unfolds, leafy vegetables like kale and spinach require additional nitrogen for their continued growth, while fruiting crops like tomatoes require additional phosphorous and potassium for blooms and fruiting. Therefore, making gradual adjustments to fertilizer types may prove advantageous over the course of its growing season.
Apply any type of fertilizer sparingly and at the appropriate time of day, since applying it during the hottest part of the day could stress and burn vegetable seedlings and transplants. As this will reduce the effectiveness of nutrients, and may force the plant to redirect energy towards producing foliage instead of fruit or flowers, it’s advised to spread and side-dress fertilizer early morning or late evening before it becomes hot. If you decide to apply fertilizers during the day, immediately water it afterward to prevent excess salt build-up and protect the roots from scorching summer heat. A thick layer of mulch will also help protect roots and reduce need for additional applications of fertilizer while limiting unnecessary nutrient accumulation.
Fall
Plants from the Brassica and Nightshade families (broccoli, kale, collard greens) are heavy feeders and require regular applications of granular fertilizer throughout their growing seasons. As these crops require more water and energy to produce flowers and fruit, their depleted nutrients quickly deplete soil reserves – it’s therefore crucial to fertilize vegetables again during fall harvest season in order to replenish these reserves for future crops.
Before planting or when the ground becomes workable, apply an initial round of organic granular fertilizer in spring. A granular organic fertilizer works well at this time of year and can either be mixed into the soil directly, or scattered around seedlings as needed.
As the season advances, add fertilizer as directed on its product label. However, take care not to overfertilize as too much fertilizer can disrupt soil balance and deprive plants of vital nutrients, leading to yellow leaves or burnt leaf tips indicating deficiency of these vital elements. Furthermore, excessive fertilization may dry out soil causing it to become salty preventing proper water absorption and leading to inefficient plant growth.
Prior to applying fertilizers in your vegetable garden, it is a best practice to conduct a soil test. This will give you an accurate idea of the optimal levels for your soil’s nutrients, and help create a schedule for when to fertilize your plants. You can perform simple soil tests yourself at home using kits available online, or send samples off to local Cooperative Extension offices for more accurate results.
Mulching can also help improve the health of any vegetable garden, as it helps retain soil moisture, protecting it from erosion caused by winter rains and helping reduce weed growth that robs vital nutrients from vegetables. Companion planting with compost or cover crops each year is another excellent way to replenish lost nutrients while improving soil quality; used properly these techniques will ensure that your garden contains sufficient nutrition for an abundant and productive harvest.
Winter
Have you been impressed by your neighbors’ lush vegetable gardens and wondered how they achieved such success? Well, the secret lies in fertilization: whether in raised beds or the ground. Organic and inorganic fertilizers will improve harvests while encouraging strong, healthy plants with improved resistance against disease and insects. However, it’s essential that you use fertilizers according to the hardiness zones in your region and the type of crops grown in them.
Most vegetable gardens need regular feedings, especially if you’re growing heavy-feeders like tomatoes, brassicas (such as kale and broccoli) and nightshades ( such as potatoes). These crops often benefit from multiple applications of fertilizer throughout their growing seasons to meet their nutrient requirements and ensure success.
Before applying fertilizers to your garden, it’s wise to conduct a professional soil test to gauge what nutrients may be missing and in what quantities. Or you could purchase commercial veggie fertilizer with an N-P-K ratio suitable for the plants in question.
Whenever using commercial veggie fertilizer, be sure to follow its directions exactly. Apply it early in spring – either prior to planting your veggies or soon after their seedlings have sprouted – so the nitrogen doesn’t have time to dissipate before being taken up by your plants.
Once your seeds or seedlings have sprouted, granular organic veggie fertilizer should still be applied lightly to their topsoil around their plants to provide some additional nutrition. Be careful not to disturb any roots when doing this and ensure it reaches every part of the root zone before watering and repeat as necessary throughout the growing season.