Fertilizer Is A Seasonal Commodity

Fertilizer is about to be passe.

Fertilizer, in simple terms, helps plants grow. It provides a bit more of what growing plants crave. In some situations, it compensates for nutrient deficiencies. Fertilizer can be organic or synthetic. Various formulations serve a variety of purposes. Custom formulations appeal to plants with discriminating taste, such as citrus, orchids and roses. Slow release fertilizer lasts for a month or two.

Of course, proper scheduling of the application of fertilizer is very important. Fertilizer can actually become toxic with excessively frequent application. Fertilizer that provides significant nitrogen to promote vegetative growth after bloom can inhibit floral growth prior to bloom. Fertilizer that promotes root growth for new plants is unnecessary for mature plants. The diets of plants are variable.

Summer lingers later here. Regardless of the weather, it is now autumn. This is when deciduous plants start the process of defoliation for their winter dormancy. Evergreen plants are less obvious about their winter dormancy. Some remain active and even bloom through autumn and winter locally. Nonetheless, cooling weather and shortening days inhibit vascular activity of almost all plants.

Except for cool season vegetables and bedding plants, not many plants benefit from fertilizer applied this late. New plants might appreciate a bit just to help them adjust to their new environment. Some deciduous plants, particularly roses, like a last late application of fertilizer as they get ready for their long winter dormancy. Lawns might want fertilizer this late or perhaps later to stay green.

Otherwise, it is getting late to utilize fertilizer.

Late application of fertilizer can be very detrimental to plants that are sensitive to cool weather. Such plants typically finish growing through summer. By autumn, their mature foliage and stems are either resilient to minor frost, or are dieing back (defoliating) for winter dormancy. Fertilizer can stimulate premature development of new growth that will be much more sensitive to even mild frost.

All Good Things In Moderation

70405thumbToo much of a good thing can be a problem. That is why bacon is not one of the four basic food groups. It is why sunny weather gets mixed with a bit of rain. It is why we can not give plants too much fertilizer. Since late last summer or autumn, there has not been much need for fertilizer. If fertilized too late, citrus and bougainvillea develop new growth just in time to be damaged by frost.

Now it is time to start applying fertilizer, but only if necessary or advantageous. Fertilizer really is not as important as the creative marketing of fertilizers suggests. It is useful for new plants, fruits, flowers, lawns and especially for vegetables, but is probably overkill for healthy and established plants. There is no need to promote growth of trees and shrubbery that are at their optimum size.

Some of the specialty fertilizers are a bit fancier than they need to be. With few exceptions, complete fertilizers are useful for most applications. As long as plants get the extra nutrients that they crave, they should not complain. They can not read the labels of the fertilizers that they receive. Plants are more likely to have problems if they get too much of something that they do not need.

Rhododendrons and azaleas might like specialty acidifying fertilizer, but should be satisfied with a complete fertilizer. Citrus might likewise appreciate fertilizer that is specially formulate for citrus, but are probably not too discriminating. Palms only want specialty palm fertilizer if they demonstrate symptoms of nutrient deficiency. (Some palms are sensitive to deficiencies of micro nutrients.)

Too much fertilizer, especially fertilizer with a good amount of nitrogen, can inhibit bloom of several plants. Bougainvillea puts more effort into vigorous shoots and foliage than into bloom if it gets strung out on nitrogen. Nasturtium will do the same. In pots and poorly drained locations, excessive fertilizer can become toxic enough to discolor foliage or even scorch the edges of large leaves.

The most justifiable uses for fertilizers now are for flowering annuals and vegetable plants. Tomato and corn plants respond very favorably to fertilizer because they are so greedy with the nutrients they require for their unnaturally abundant production. (In the wild, the ancestors of tomato and corn do not really produce like garden varieties do.) Flowers, of course, take a lot of resources too.