Marianne's Response

green tower boxwood

Hi,
I am on a small top floor condo in central coastal CA near Monterey area. (I saw that PlantersPlace address is in Bloomington where I went to school and grew up in lush greenery. I think I am always trying to make alittle of that happen here!!)
I have decks, no ground, so containers only.
Front deck is SW facing, but with entry eave and high hill in front of the complex, it only gets around 5-6 hrs of afternoon-evening sun.
Side deck, SE, is .completely open, full sun until late afternoon.
For 10 or so years 3, 7-8ft. italien blue cyprus in pots added a dark green foresty note, then got too shaggy so found a new home in someone’s privacy hedge. None of the beautiful flowering things that I tried , did well. I am reluctantly learning to apppreciate succulents, but they ain’t no peonies, dahlias or hydrangeas.

After “clearing the decks” again 18 months ago, I bought ($!!) 3, 4-5 ft. Monrovia green tower boxwood for the now vacant “tree corners”–2 on side deck 1 on the front. I transplanted the 2 into 20″ diam by 17″ hi pots with new potting soil. The one in the front is still in it’s 5gal growers pot. They all have good drainage. None of the 3 are doing well . Wimpy green with sprinklings of yellow, orange or brown leaves throughout, has flowers/ seeds, but little if any new growth. They have gotten some Miracle grow solution every 2-4 weeks. But since they looked poorly I did not want to overfertilize.
Someone said spray with epsom salt sol. 1T/gal. Sprayed the foliage on Sun. Bought Osmocote on Mon. and yesterday (Wed.) applied 1 scoop (3T) to each of the bigger pots and 1/2 scoop to the boxwood that is still in the growers pot.
All suggestions or advice will be welcome I am wondering if I just need to find someone to help me repot with new or different soil…?? I think of boxwoods as being a not-picky workhorse of plants!! Help!

Thank You so much,
Kathleen

Before I ordered, the rep said the Osmocote plus pink bag would be 19-6-12. He even went back to look.
Mine says 15-9-12. Why is that – and what would work best for me? Oh, and it says for all plants, would dosage be the same for the succulents

Posted by Kathleen Wiberg on September 29, 2019

Marianne's Response

Well, first congratulations on creating a green oasis on your deck. My thought is that you have given your boxwood too much liquid fertilizer. These are tough evergreens that do not require fast acting plant foods like Miracle Grow every two to three weeks. The result will be overproduction of flowers and seeds at the expense of green leaves. The brown leaves are common during winter months but in your case they may be a sign that the soil has become too "basic" due to the over fertilizing with the Miracle Grow. Evergreens like a soil that is slightly acidic. But no need to worry. No need to repot. Time will cure this problem as heavy winter rains should wash out the excess nutrients and I predict healthy green plants in the spring. The Osmocote does not need to be removed as it becomes available very slowly. I suggest water but no fertilizer for 18 months.  Then use Osmocote at half strength just once a year in late spring. The formula on the Osmocote bag changes as new developments in plant nutrition are discovered to make the formula most effective for a wide range of plants. The dosage of Osmocote for succulents should be half the recommended rate on the package. Succulents, like boxwoods are not heavy feeders. You are only guilty of loving your plants too much and over feeding. Roses, annuals and perennials are the heavy feeders that love fast acting plant foods like Miracle Grow.  Keep calm and grow on.  Marianne Binetti

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