Gifts for the Gardener Who Has Everything

A worm bin that works indoors year-round, which is the only real option for an apartment -- and worm castings are better than compost anyway.

Vermicomposting is the answer to two problems at once: no outdoor space, and winter. A worm bin lives under a sink or in a garage and keeps working at room temperature when an outdoor pile has gone cold and dormant.

The stacking system does the sorting for you. Worms finish a tray and migrate up toward the fresh food in the tray above, leaving finished castings behind to lift off.

Two habits make the difference between an odor-free bin and a bad experience: feed small amounts, and keep the bedding damp rather than wet. Smell is almost always overfeeding.

Skip it if: the idea of keeping worms in the house is a hard no. It works, it does not smell, and it is still not for everyone.

A worm bin without worms is a plastic box. Red wigglers are the composting species -- garden earthworms will not do this job.

The species matters and beginners often get this wrong. Red wigglers live in decaying organic matter at the surface, which is exactly what a worm bin is. The nightcrawlers you dig up in the yard live in soil burrows and will try to escape a bin, or die in it.

Start with a modest quantity and let them multiply. Worm populations track their food supply, so a starter batch in a well-run bin grows to fill it within a season.

Order for a mild week. They ship as live animals in a box, and a heat wave or a hard freeze in transit is the main reason a delivery arrives dead.

Skip it if: your bin will live somewhere that freezes or bakes. Worms are livestock and they die in both directions.

The cheapest accessory that changes decisions: it tells you the overnight low and the midday high, not the temperature at the moment you happened to look.

Every greenhouse decision -- when to sow, when to vent, whether you need a heater, whether the frost cloth is doing anything -- depends on a number most owners never measure: the overnight low inside the structure.

A min/max thermometer records the high and low since you last reset it, so a morning glance tells you what happened while you slept. That turns guessing into knowing, for the price of a bag of compost.

Hang it at plant height and out of direct sun. A thermometer in a sunbeam reports the sunbeam, not the greenhouse.

Skip it if: nothing. If you own a greenhouse and not one of these, you are guessing about the only variable that matters.

Two chambers is the whole point: you keep adding to one side while the other finishes, so you get a batch out instead of a bin that is never quite ready.

The single-chamber problem is why most first composters give up. You keep adding kitchen scraps to the same bin, so the contents are always part-finished, and you can never take any out.

Two chambers solves it mechanically. Fill side A until it is full, then switch to side B and leave A alone. By the time B is full, A is finished compost you can empty in one go. In warm weather that cycle runs in a matter of weeks.

Understand the capacity limit going in. Around 37 gallons total is generous for kitchen scraps from a household, and small if you also want to compost lawn clippings and autumn leaves. Those belong in an open bin.

Skip it if: you generate a lot of yard waste. A tumbler is volume-limited by design, and a big open pile handles leaves and grass far better.

The concentrate: a small amount worked into the root zone does more than a much larger volume of ordinary compost.

Castings are what a worm bin produces, and they are the most concentrated common soil amendment available in a bag. The useful property is that they are gentle -- unlike fresh manure, castings will not scorch a seedling.

Use them where roots will find them: a handful in each planting hole, or a thin layer raked into the top few inches before planting. Spreading them thinly across an entire bed is largely wasted.

If this becomes a regular purchase, that is the argument for a worm bin. You would be making the same material at home from material you currently throw away.

Skip it if: you are trying to add volume. Castings are an amendment, not a fill -- a bed of pure castings is both wasteful and too dense.

Thick enough to pick up full without folding, which is the entire complaint about cheap trays and the reason these cost more.

Anyone who has carried a cheap 1020 tray full of wet compost knows the failure mode: it folds in the middle and the seedlings go on the floor. Heavy-gauge trays do not do that.

The 1020 name is a standard footprint, roughly 10 by 20 inches, and it is worth sticking to. Every humidity dome, heat mat, cell insert and shelf is built around it.

Buy a couple of solid, undrained trays alongside the drained ones. A solid tray underneath lets you water from below, which is gentler on small seedlings than watering from above and keeps the leaves dry.

Skip it if: you start one tray a year. The economics only work once you are reusing them season after season.