I planted some mazus reptans last year, and it did well, filling in the area I needed. After a cold Utah mountain winter and a ton of snow, it has a thick mat of brown, dead stuff. The new growth is coming, under all the dead stuff. Should I rake away last years' growth, or just be patient and let the new growth come up through it?
Yes, you should prune any dead or damaged parts of the plants.
Gently raking can remove some of the dead material but you should use caution not to dislodge the root sytem.
Trimming by hand may be necessary for a good clean up of the ground cover.
https://www.gardeningknowhow.com/ornamental/groundcover/mazus/growing-mazus-reptans.htm
I planted Mazus last year and it spread and bloomed as advertised. However, after a relatively cold winter (Maryland area close to DC) the majority of the plants have turned brown and only the outer portions of the plant have new blooms. Is this normal and given the warmer weather in late April and early May the brown portion of the plant will return to its original green growth and blooms will hopefully reappear. If this is not the case then is this a sign that the plant has died and I should purchase new plants? Thanks, Gene
It will, usually, recover. There is no action needed except for occasional fertilization. This article will give you more information on the care of these: https://www.gardeningknowhow.com/ornamental/groundcover/mazus/growing-mazus-reptans.htm
(I live in Maryland in a suburb of DC) I no longer have blooms but the plants are a yellowish/green and not the rich green color of previous years. Can you give me advice on how to address these two issues? Thanks
Depending on your weather, blooming certainly can occur both earlier and later than its normal summer bloom time.
Yellowing foliage can be due to watering issues, too much or too little, pests and diseases.
This article will help refresh you on the care requirements.
https://www.gardeningknowhow.com/ornamental/groundcover/mazus/growing-mazus-reptans.htm
I am planning on planting Mazus between stepping stones. There is some kind of gravel under the soil where the stepping stones are situated. I need to make sure there is enough soil under the Mazus.
Mazus is suitable for a rock garden, the gaps in a rock wall, and between stepping stones, so it should be fine in your soil. You would only plant it as deep as it is already growing in a container. You could work in some compost to be sure there is enough soil.
https://www.gardeningknowhow.com/ornamental/groundcover/mazus/growing-mazus-reptans.htm