|I have gotten many different responses to this question and need some help! Last year I planted 3 Redbud trees in my yard. I have a professional arborist organization fertilize all my trees annually. They informed me that Redbuds need sulphur to maintain good health. They told me to go to a nearby nursery/garden shop and purchase some there. When I went to the nursery/garden shop they weren't sure what to give me. I've made two trips so far, back and forth with things they thought I needed. On the last trip they gave me "garden sulphur". When I read the bag, I got scared. There were lots of precautions and only instructions to use the product as an insecticide. I called The Chicago Botanic gardens hotline - two different people told me two opposite things. One said Yes they need sulphur, another said leave the trees alone. I don't know what to do and I don't know what to purchase, if I need to fertilize them. Help!|
|Redbuds are well adapted to many soil types except to permanently wet ones; he also specifically indicates that they tolerate a wide range of pH, so it is unlikely that you would need to do anything drastic to your soil in order to get these trees to grow. (They are in fact native over a wide range of climates and conditions.) He does point out that they should be kept vigorous by regular watering and fertilization. The amount and type of fertilizer would be determined by the results of some basic soil tests; your county extension (223-8627) should be able to help you with the tests and interpreting the results. However, in early spring you could apply some compost and/or a complete fertilizer such as 5-10-5 in granular form broadcast around the root zone of the plant according to the label instructions.
This, combined with maintaining several inches of organic mulch year round, should be sufficient to feed the soil and keep the tree healthy. Watering is probably more critical than anything else in establishing new trees. Water as needed to keep the soil moist yet not soggy, taking care to water deeply less often, rather than applying a daily light sprinkling. Good luck with your trees!