I know you can always fertilize with organic fertilizer, but the the cost is much higher. So may be just do not bother with the fertilizing?

Planting fruit trees in a home orchard surrounded by lawn grass is certainly common but I would be cautious about lawn fertilization. Lawn fertilizers - either synthetic (chemical) or organic - contain a high proportion of nitrogen, which may not be the most desireable nutrient for a flowering and fruiting plant. Nitrogen tends to encourage rapid stem growth and foliar development, to the expense of flower and fruit production.

Fertilize the lawn lightly if necessary, focusing on an organic product (lower N levels and slower release) or better yet, use a mulching mower. And repeated use of weedkillers can have detrimental effects on any established plant in the vicinity, so I'd tread very carefully there.

bags

I do use a mulching mower too, and spot treating weeds uses just what is needed and no more. Once a year I use a more complete chemical fertilizer. I'm thinking if switching to turf trust, what an excellent product! 39 bucks a bag though! Well once every two years would make sure grass has all it needs. Fertilize also with the organic at the end of the year, and the following year. Turf Trust lasts like 14 weeks, again an awesome product.

Turf Trust Lawn Fertilizer is a premium lawn fertilizer that slowly feeds your lawn for twelve to fourteen weeks. Turf Trust helps create a thicker, self-sustaining lawn by slowly feeding essential nutrients for root development.

Turf Trust is the only fertilizer to use the compound CDU (Crotonylidene Diurea) as a nitrogen source

CDU also helps control lawn diseases such as Brown Patch, Fusarium Blight, and Pythium

Contains Potassium - which helps thicken cell walls and roots develop

Turf Trust is great for sunny and shady lawns

Contains several different sources of nitrogen

40% water insoluble nitrogen - maximizing long-term affects of the product

Turf Trust Classic - 2% Phosphate - helping eliminate the risk of runoff

Turf Trust also has a 0% Phosphate formula for areas with a phosphate ban

12% Potassium implements good root development and cell wall growth

Lawn fertilizers without herbicide were the same as all purpose fertilizer until recently. Environmental groups found most surface-applied lawn fertilizer is washed off into the drainage system where the phosphorus feeds dangerous algae blooms. Anything now marketed as a lawn fertilizer doesn't contain phosphorus.

The effects of lawn fertilize on trees probably depends more on how porous your soil is and the grade of the land. In any case, it would be best to check soil samples once in awhile and target the tree with a correction to that. Trees might only need additional phosphorus in areas where lawn fertilizer is used.

Other than general fertilizer, we normally use pre- and post-emergent weed killers. I have not used any fertilizer in my fruit/garden areas for several years.

As far as lawn fertilizer being safe for edible, yes absolutely, it's only fertilizer! No secret magic poison fertilizer for grasses exist. The same chemicals are used to make fertilizer for edibles. Depends what the factory is tooled for at the time. It still uses the same stuff.
Reminds me of the statement that somehow battery acid which is sulfuric acid, has heavy metals. Well if it did, your batteries would explode! It is perfectly safe to use to acidify water.

Trees need fertilizer, especially when young, when older they often can find food on their own, but it never hurts, and can greatly increase yield, health, and longevity of your trees to fertilize. A well fed tree has more chance of surviving attacks by insects, fungi etc. Borers in general go after weak trees. Some go after any tree, but they do look for weak trees. Natures way...

Boy, I wish I had a dime for every time I've heard that statement! And it is not particularly accurate :-) Plants manufacture their own food - that's what the process of photosynthesis does. What they DO need is access to basic nutrients to facilitate this process and depending on current soil conditions, those nutrients may very likely already be present. Remember that no one is out there in the wilds and natural areas applying fertilizer and the plants grow just fine! It is never a good idea to apply fertilizer without at least a basic soil test to determine what, if anything, may be missing or deficient. The application of fertilizer unnecessarily may cause more problems than it it solves.

Gratuitous applications of fertilizer just "because" or in the mistaken belief that plants must be "fed" are fabrications of the fertilizer industry. In most cases, other than containerized plants, harvested edibles and annuals, woody plants seldom need additional fertilizer. And often the application of a good organic mulch will adequately supplement what might be required.

Plants will generally tell you if they require nutrient supplementation - growth will be slow or stunted, foliage discolored or small and flowering or fruiting light. If that is the case, have a professional soil test done to determine what may be amiss. And if new to the area or gardening in general, a baseline soil test is a good idea to get you on the right track. Once you've determined that any nutrient deficiency exists, THEN you can fertilize to address that need. But fertilizing just for the belief that it is the proper thing to do is not an acceptable horticultural practice and can lead to problems. Plants that are over fertilized tend to be less cold and drought tolerant, more disease prone and overly susceptible to insect predation.

btw, lots of lawn fertilizers contain phosphorus, but in relatively low percentages. Phosphorus is still an essential plant nutrient and may not be present in adequate levels in all soils, especially those with recent construction or other disturbance or removal of native topsoil.

Most of the folks have "backyard" fruit area, which was a lawn area before. It does not make sense to rid of the lawn when you plant the fruit trees. The needs of the turf grass is very different from that of fruit trees.

For lawn, you want to look good. If your lawn is 30% weeds and your neighbor has a almost perfect lawn, you are in trouble (from spouse etc.).

For my front yard, I spread fertilizer about 2-3 times a year. My neighbor does about 6 times a year. But I've not put any chemical in my fruit/garden area for several years. Clearly I have a lot more weeds in my fruit area. Do I care? Of course I care. When I have time, I may pick up my hand weeder and take out a few weeds. But most of the time I just ignore them. I just tell myself I do not want any chemicals in my edible areas.

Of course I'm still learning. Some of the chemicals are clearly needed, such as fruit tree sprays. Also, since my fruit/garden area is at the end of the slope area, I would want to know if the chemicals can be washed to my edible area.

You can say what you will, link to tutorials and research, I'm talking from what I do, not what others did. My own experience of growing for 45 years.

I think there is nothing wrong with being health conscious. We Americans throw so much toxic waste on our front yard and back yard. All the chemicals get washed to the river and to our water resources. All the toxic stuff can certainly come back and get in our food, etc.

This is one of the main reasons we grow our own fruits, vegetable and other food. Gardening is fun. Also we know what we grow is the most healthy food we can get.

The idea situation is to fertilize the spur leaves without fertilizing the vegetative shoots so the applications need to be made in earliest fall (very late summer) or early spring with a fast release form of N.

Commercial growers often hit the spur leaves with soluble N in early spring when spur leaves first come out. This not only improves the size and quality of the fruit but helps assure a crop the next year.

It is a good idea to test your soil before pouring on fertilizer beyond just maintenance levels. Usually phosphorous is not needed and routinely adding it may create an excess of it over time, tying up other nutrients. It is also a chemical that often ends up in streams and lakes creating blooms that starve fish for oxygen.