# Best Window Boxes Source: https://balconygardenpicks.com/best/best-window-boxes Updated: 2026-09-22 Publisher: Balcony Garden Picks. Our score is an editorial rating out of 10 (fit 35%, features 25%, build 20%, value 20%), not a customer rating. Method: https://balconygardenpicks.com/how-we-research#our-score Length is the specification to settle first, and it is the one most people guess at. Boxes in this category are sold in fixed sizes, typically 24 or 30 inches, and they are usually bought in twos and fours so a run can be built up along a sill or rail; measure the span you want to fill and divide by those increments rather than ordering a single box and hoping. Leave a finger's width between boxes so they can be lifted out individually. The next decision is construction. Open metal frames fitted with a coco liner drain freely, breathe at the sides and look softer, but the liner dries out fast in wind and needs replacing every year or two. Solid boxes hold moisture much longer and are the better choice on an exposed upper floor, provided they have drainage holes; if they do not, you will be drilling them. Then think about weight, because this is the part that catches people out: wet compost is heavy, and a planted 24-inch box needs brackets or rail hooks rated well beyond the empty weight printed on the listing. Check how the box attaches, whether it clamps to a round or flat rail and whether the clamp adjusts, and add a drip tray or plan the runoff so it does not land on the balcony below. Powder-coat colour is the least important thing here. ## Picks ### 1. VOXOR Railing Planter Boxes Heavy Duty Window Box 24 Inch 2 Pack Our score: 8.4/10 (Fit for the job 9/10 · Features and specs 8/10 · Build and materials 8/10 · Value 8/10) VOXOR's heavy duty 24 Inch railing planter window boxes in a 2 Pack for herbs and trailing flowers. Pros: - Heavy Duty build holds wet soil securely on the railing - 24 Inch length fits a row of herbs or bedding plants - 2 Pack lets you balance planters on both sides of a balcony Cons: - Measure your railing width before ordering this planter - Filled boxes put extra weight on older railings Details: https://balconygardenpicks.com/product/B0DSK7NKSR ### 2. DUNCHATY 24 Inch Railing Planter Box 4 Pack Metal Window Flower Box Our score: 8.4/10 (Fit for the job 9/10 · Features and specs 8/10 · Build and materials 7/10 · Value 9/10) DUNCHATY's 4 Pack of 24 Inch metal railing planter window flower boxes for lining a whole balcony. Pros: - 4 Pack fills a long railing with matching planters - Metal frame is durable for outdoor use through rain and sun - 24 Inch boxes suit herbs, lettuce and trailing flowers Cons: - Four filled boxes add significant weight to the railing - Potting soil is not included, so budget for that separately Details: https://balconygardenpicks.com/product/B0CZQ7Z764 ### 3. Harmiden 30" Window Box Railing Planter with Coco Liner 2 Pack Our score: 8.2/10 (Fit for the job 9/10 · Features and specs 8/10 · Build and materials 7/10 · Value 8/10) Harmiden's 30" window box railing planter with coco liner in a 2 Pack for flower-filled balconies. Pros: - Coco Liner drains well and gives a natural cottage look - 30" length is longer than typical boxes for fuller displays - 2 Pack covers a larger stretch of railing Cons: - Coco liners dry out quickly and need frequent watering - Liners wear out and need replacing every few seasons Details: https://balconygardenpicks.com/product/B09JNZDG1Z ### 4. WIMART Window Box Railing 24 Inch Black Metal 4 Pcs Our score: 8.0/10 (Fit for the job 8/10 · Features and specs 8/10 · Build and materials 7/10 · Value 9/10) WIMART's black metal 24 Inch window box railing planters in a set of 4 Pcs. Pros: - Black metal finish looks sleek on modern railings - 4 Pcs set covers several railing sections - 24 Inch length fits most standard railing spans Cons: - Add a liner to stop soil washing out through gaps - Metal boxes can heat soil quickly on railings in full afternoon sun Details: https://balconygardenpicks.com/product/B0BLMP4W6V ### 5. Harmiden Window Box Deck Railing Planter 24 Inch 2 Pack Our score: 7.6/10 (Fit for the job 8/10 · Features and specs 7/10 · Build and materials 7/10 · Value 8/10) Harmiden's 24 Inch window box deck railing planter in a 2 Pack for compact railing gardens. Pros: - 24 Inch size fits shorter railings and deck edges - 2 Pack gives a matching pair of planters - Designed for both window boxes and deck railings Cons: - Add a liner separately to prevent soil washing through - Smaller boxes hold less soil and dry out faster Details: https://balconygardenpicks.com/product/B097XQZKT5 As an Amazon Associate I earn from qualifying purchases.