I do not believe it is cedar hawthorn rust because it is just the tips of the leaves that are browning out and there are no other spots on the rest of the leaves. However, I did notice a few branches with cankers at the end of last winter but I was unaware that they should be trimmed off and...
I would let it dry out completely before planting it. Then I would put some real good potting soil in a pot and plant the seed. Keep it moist not soggy. Keep a grow light on it in the winter.
Yeah a small, rosy red apple with a rather hard, extremely tart flesh. Crabapples, available during the fall months, are too sour for out-of-hand eating but make outstanding jellies and jams.
Well the prolonged freezes seldom concern gardeners living in U.S. Department of Agriculture Plant Hardiness Zone 9, where winter lows typically range from 20.