Japanese Holly (Ilex crenata) is nearly identical to Boxwood, with small, spineless leaves and dense branching. While not without their own set of vulnerabilities (as every shrub has), hollies are not susceptible to the insects and diseases of boxwood save for the near-universal threat of root rot in poorly-drained soils.

A similar option would be a dwarf variety of Yaupon Holly (Ilex vomitoria); this is the closest we would have to a native species alternative. They are native to the southeastern U.S., just not in MD. Winter temperatures used to be a problem for reliable hardiness in this species here, but these days it's unlikely we'll regularly experience any overly-cold extremes that will damage them, especially if the planting location is sheltered near a wall or faces south/west. It's a risk, still, but probably not a high one.

A dwarf variety of Inkberry holly (Ilex glabra) can also work, though the foliage is a little bit bigger (still small for a holly, and also spineless). There will be a trade-off in short-term and long-term benefits between opting for a standard variety that will fill-in that 3 to 5' desired size fairly quickly, and a more dwarf variety that will take longer but which won't outgrow the space. (For instance, industry standard variety 'Shamrock', which tags tend to say will get about 5', eventually actually reach around 7' tall when untrimmed.) Dwarf options are fairly new and include the varieties named 'Gem Box' and 'Strong Box'. While Japanese and Yaupon hollies can be trimmed as needed, Inkberry is best minimally trimmed or left alone, since their interiors naturally don't stay as dense and therefore they don't look as nice when shearing shortens them considerably.

Most broadleaf evergreen foliage won't be as small as that of Boxwood, but you could look into less-common options like:

• Osmanthus delavayi - like the Yaupon, also hardy to zone 7, so a little risky if we ever experience zone 6 winter conditions again (or if the site is quite exposed to winter winds); otherwise, provides fragrant flowers in spring and foliage is fairly small, at least for an Osmanthus; definitely large enough, and would require occasional trimming to keep around 5'
• Osmanthus heterophyllus 'Kaori Hime' (a.k.a. 'Party Princess') - like the above, but with fall blooms instead, and a bit more hardy; mature height roughly 3'
• Glossy Abelia (Abelia x grandiflora) - not 100% evergreen if the winters are dry or windy, but they can be when in a sheltered spot; blooms from around June/July into autumn; heights vary by cultivar but are within your preferences; of the four species listed here, this will be the easiest to find by far
• dwarf forms of Waxmyrtle (Myrica, a.k.a. Morella) - both Northern and Southern look alike and have dwarf cultivars, though like the Osmanthus above, they can be hard to find; names include 'Don's Dwarf', 'Bobbee', 'Morton Male' and 'Silver Sprite'

There are many more options - too many to list fully here - among non-evergreen shrubs or evergreens with notably larger leaves.

Miri

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