Frequently Asked Questions

Questions people actually ask

How long does a self-watering planter last between refills?

It is the reservoir capacity divided by how much water the plant uses per watering. For a 6-inch tropical houseplant using about 350 ml per thorough watering at once or twice a week, a 5-liter reservoir computes to 49 to 98 days and a 1-liter reservoir to about 10 to 20 days. The full calculation is published.

Do watering globes actually work?

Within their volume. A typical small globe holds about 118 ml, which on a 6-inch tropical houseplant is one to two days, not the one to two weeks usually advertised. On a 4-inch pot the same globe computes to four to eight days, and a 500 ml globe on a 6-inch pot computes to five to ten. The arithmetic is here.

How often should I water my houseplants?

Virginia Cooperative Extension publishes two bands: tropical houseplants sometimes once or twice a week, and succulents and cacti once or twice a month. But check rather than count days, because water use changes with season, light, pot size and how root-bound the plant is. The reference page has the detail.

Is my plant overwatered or underwatered?

Feel the soil two inches down, feel the leaves, and lift the pot. Wet soil, mushy leaves and a heavy pot mean overwatered. Dry soil, brittle leaves and a light pot mean underwatered. Wilting alone tells you nothing, because both problems cause it. The full table is here.

What is the best way to water plants while on vacation?

Match the reservoir to the trip. For a week on 6-inch indoor pots, a terracotta spike on a 750 ml wine bottle computes to 8 to 15 days. For a month, or for many plants, a drip kit with a 5-gallon reservoir is the only option with the volume. The section is organized by trip length.

How long can houseplants go without water?

Tropical foliage plants are published at once or twice a week, so most show stress within a week and real damage by two. Succulents and cacti are published at once or twice a month and can genuinely be left for a month. More detail, including the pot-size effect.

Do self-watering pots cause root rot?

Not when used as designed. An air gap between the reservoir and the root zone keeps roots out of standing water. Rot follows from top-watering as well as filling the reservoir, overfilling past the designed level, or using a mix too dense to drain. We go through the mechanism in full.

Are self-watering pots worth the money?

For a tropical foliage houseplant owned by someone who forgets, yes. For succulents, for people who overwater, and for covering a vacation, no - each of those has a cheaper and better answer. The honest yes-and-no is here.

Are soil moisture meters accurate?

Not in a calibrated sense. They measure electrical conductivity on a relative 1-to-10 scale, and no meter in the category publishes an accuracy figure or a calibration method. They are reliable for comparing a pot against itself over time, which is what the decision needs. The full answer is here.

Do I need a moisture meter, or is my finger enough?

For pots up to about 6 inches your finger is as good, and extension guidance recommends pushing it one to three inches into the mix. A meter earns its place on deep pots, on large collections, on root-bound plants, and for fast diagnosis of a sick plant. Compared properly here.

Which is better, a watering globe or a terracotta spike?

The spike, for pots of 6 inches or more. The reservoir is a bottle you supply, so it holds six to seventeen times as much, and terracotta throttles flow by soil moisture where a globe does not throttle at all. The head to head is here.

Can I save an overwatered plant?

Often, if you catch it before the whole root system is gone. Stop watering, unpot it, cut rotted roots back to firm white tissue, reduce the foliage to match, repot into fresh open mix in a clean draining pot, then leave it alone until the mix dries down. The full sequence is here.

What causes root rot in houseplants?

Fungal and fungus-like organisms including Pythium, Phytophthora, Rhizoctonia and Fusarium, which thrive in wet, poorly drained soil and attack weakened plants. They are commonly present already - the wet conditions are what let them take hold. The treatment is here.

What are the hardest houseplants to kill?

Plants in the succulent cadence band, published at once or twice a month: snake plant, ZZ plant, jade, hoya and cacti. That band is four times wider than the tropical foliage one, which is your margin for being late. The ranking is here.

How long should I bottom water a plant?

Fifteen to thirty minutes for most pots, until the surface of the mix darkens. Never more than about 60 minutes - extension guidance gives that as the limit for a container standing in water. Including the salt build-up nobody mentions.

Have you tested any of these products?

No, and we say so on every page. There is no lab and no test bench. What we do instead is compile every published specification, attribute each figure, and compute refill intervals from published inputs so anyone can check the arithmetic. The method is published in full.

How does Wilt & Water make money?

Affiliate commission. We are a participant in the Amazon Services LLC Associates Program and earn from qualifying purchases made through our links. It does not change what you pay, and selection is driven by published specifications rather than commission rate. The disclosure lists the specifics.

Why do some products here show no price?

Because we only display a price we can currently verify. Prices come from a live data layer with a capture date, and if that data is more than 48 hours old the number disappears and the button reads “Check price on Amazon” instead. A stale number is worse than none, because it looks like information.

Why does a product page say the capacity is not published?

Because the manufacturer does not publish it and we will not estimate it. Reservoir capacity is the number that decides how long a product lasts, and inventing a numerator produces a real-looking answer with nothing behind it. Where the figure is missing we say so and compute nothing.